Bug Summary

File:llvm/include/llvm/Bitstream/BitstreamReader.h
Warning:line 221, column 39
The result of the right shift is undefined due to shifting by '64', which is greater or equal to the width of type 'llvm::SimpleBitstreamCursor::word_t'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name BitcodeAnalyzer.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/lib/Bitcode/Reader -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/lib/Bitcode/Reader -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/lib/Bitcode/Reader -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/build-llvm/lib/Bitcode/Reader -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0=. -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-08-28-193554-24367-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp

/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp

→
1//===- BitcodeAnalyzer.cpp - Internal BitcodeAnalyzer implementation ------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "llvm/Bitcode/BitcodeAnalyzer.h"
10#include "llvm/Bitcode/BitcodeReader.h"
11#include "llvm/Bitcode/LLVMBitCodes.h"
12#include "llvm/Bitstream/BitCodes.h"
13#include "llvm/Bitstream/BitstreamReader.h"
14#include "llvm/Support/Format.h"
15#include "llvm/Support/SHA1.h"
16
17using namespace llvm;
18
19static Error reportError(StringRef Message) {
20 return createStringError(std::errc::illegal_byte_sequence, Message.data());
21}
22
23/// Return a symbolic block name if known, otherwise return null.
24static Optional<const char *> GetBlockName(unsigned BlockID,
25 const BitstreamBlockInfo &BlockInfo,
26 CurStreamTypeType CurStreamType) {
27 // Standard blocks for all bitcode files.
28 if (BlockID < bitc::FIRST_APPLICATION_BLOCKID) {
29 if (BlockID == bitc::BLOCKINFO_BLOCK_ID)
30 return "BLOCKINFO_BLOCK";
31 return None;
32 }
33
34 // Check to see if we have a blockinfo record for this block, with a name.
35 if (const BitstreamBlockInfo::BlockInfo *Info =
36 BlockInfo.getBlockInfo(BlockID)) {
37 if (!Info->Name.empty())
38 return Info->Name.c_str();
39 }
40
41 if (CurStreamType != LLVMIRBitstream)
42 return None;
43
44 switch (BlockID) {
45 default:
46 return None;
47 case bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID:
48 return "OPERAND_BUNDLE_TAGS_BLOCK";
49 case bitc::MODULE_BLOCK_ID:
50 return "MODULE_BLOCK";
51 case bitc::PARAMATTR_BLOCK_ID:
52 return "PARAMATTR_BLOCK";
53 case bitc::PARAMATTR_GROUP_BLOCK_ID:
54 return "PARAMATTR_GROUP_BLOCK_ID";
55 case bitc::TYPE_BLOCK_ID_NEW:
56 return "TYPE_BLOCK_ID";
57 case bitc::CONSTANTS_BLOCK_ID:
58 return "CONSTANTS_BLOCK";
59 case bitc::FUNCTION_BLOCK_ID:
60 return "FUNCTION_BLOCK";
61 case bitc::IDENTIFICATION_BLOCK_ID:
62 return "IDENTIFICATION_BLOCK_ID";
63 case bitc::VALUE_SYMTAB_BLOCK_ID:
64 return "VALUE_SYMTAB";
65 case bitc::METADATA_BLOCK_ID:
66 return "METADATA_BLOCK";
67 case bitc::METADATA_KIND_BLOCK_ID:
68 return "METADATA_KIND_BLOCK";
69 case bitc::METADATA_ATTACHMENT_ID:
70 return "METADATA_ATTACHMENT_BLOCK";
71 case bitc::USELIST_BLOCK_ID:
72 return "USELIST_BLOCK_ID";
73 case bitc::GLOBALVAL_SUMMARY_BLOCK_ID:
74 return "GLOBALVAL_SUMMARY_BLOCK";
75 case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID:
76 return "FULL_LTO_GLOBALVAL_SUMMARY_BLOCK";
77 case bitc::MODULE_STRTAB_BLOCK_ID:
78 return "MODULE_STRTAB_BLOCK";
79 case bitc::STRTAB_BLOCK_ID:
80 return "STRTAB_BLOCK";
81 case bitc::SYMTAB_BLOCK_ID:
82 return "SYMTAB_BLOCK";
83 }
84}
85
86/// Return a symbolic code name if known, otherwise return null.
87static Optional<const char *> GetCodeName(unsigned CodeID, unsigned BlockID,
88 const BitstreamBlockInfo &BlockInfo,
89 CurStreamTypeType CurStreamType) {
90 // Standard blocks for all bitcode files.
91 if (BlockID < bitc::FIRST_APPLICATION_BLOCKID) {
92 if (BlockID == bitc::BLOCKINFO_BLOCK_ID) {
93 switch (CodeID) {
94 default:
95 return None;
96 case bitc::BLOCKINFO_CODE_SETBID:
97 return "SETBID";
98 case bitc::BLOCKINFO_CODE_BLOCKNAME:
99 return "BLOCKNAME";
100 case bitc::BLOCKINFO_CODE_SETRECORDNAME:
101 return "SETRECORDNAME";
102 }
103 }
104 return None;
105 }
106
107 // Check to see if we have a blockinfo record for this record, with a name.
108 if (const BitstreamBlockInfo::BlockInfo *Info =
109 BlockInfo.getBlockInfo(BlockID)) {
110 for (unsigned i = 0, e = Info->RecordNames.size(); i != e; ++i)
111 if (Info->RecordNames[i].first == CodeID)
112 return Info->RecordNames[i].second.c_str();
113 }
114
115 if (CurStreamType != LLVMIRBitstream)
116 return None;
117
118#define STRINGIFY_CODE(PREFIX, CODE) \
119 case bitc::PREFIX##_##CODE: \
120 return #CODE;
121 switch (BlockID) {
122 default:
123 return None;
124 case bitc::MODULE_BLOCK_ID:
125 switch (CodeID) {
126 default:
127 return None;
128 STRINGIFY_CODE(MODULE_CODE, VERSION)
129 STRINGIFY_CODE(MODULE_CODE, TRIPLE)
130 STRINGIFY_CODE(MODULE_CODE, DATALAYOUT)
131 STRINGIFY_CODE(MODULE_CODE, ASM)
132 STRINGIFY_CODE(MODULE_CODE, SECTIONNAME)
133 STRINGIFY_CODE(MODULE_CODE, DEPLIB) // Deprecated, present in old bitcode
134 STRINGIFY_CODE(MODULE_CODE, GLOBALVAR)
135 STRINGIFY_CODE(MODULE_CODE, FUNCTION)
136 STRINGIFY_CODE(MODULE_CODE, ALIAS)
137 STRINGIFY_CODE(MODULE_CODE, GCNAME)
138 STRINGIFY_CODE(MODULE_CODE, COMDAT)
139 STRINGIFY_CODE(MODULE_CODE, VSTOFFSET)
140 STRINGIFY_CODE(MODULE_CODE, METADATA_VALUES_UNUSED)
141 STRINGIFY_CODE(MODULE_CODE, SOURCE_FILENAME)
142 STRINGIFY_CODE(MODULE_CODE, HASH)
143 }
144 case bitc::IDENTIFICATION_BLOCK_ID:
145 switch (CodeID) {
146 default:
147 return None;
148 STRINGIFY_CODE(IDENTIFICATION_CODE, STRING)
149 STRINGIFY_CODE(IDENTIFICATION_CODE, EPOCH)
150 }
151 case bitc::PARAMATTR_BLOCK_ID:
152 switch (CodeID) {
153 default:
154 return None;
155 // FIXME: Should these be different?
156 case bitc::PARAMATTR_CODE_ENTRY_OLD:
157 return "ENTRY";
158 case bitc::PARAMATTR_CODE_ENTRY:
159 return "ENTRY";
160 }
161 case bitc::PARAMATTR_GROUP_BLOCK_ID:
162 switch (CodeID) {
163 default:
164 return None;
165 case bitc::PARAMATTR_GRP_CODE_ENTRY:
166 return "ENTRY";
167 }
168 case bitc::TYPE_BLOCK_ID_NEW:
169 switch (CodeID) {
170 default:
171 return None;
172 STRINGIFY_CODE(TYPE_CODE, NUMENTRY)
173 STRINGIFY_CODE(TYPE_CODE, VOID)
174 STRINGIFY_CODE(TYPE_CODE, FLOAT)
175 STRINGIFY_CODE(TYPE_CODE, DOUBLE)
176 STRINGIFY_CODE(TYPE_CODE, LABEL)
177 STRINGIFY_CODE(TYPE_CODE, OPAQUE)
178 STRINGIFY_CODE(TYPE_CODE, INTEGER)
179 STRINGIFY_CODE(TYPE_CODE, POINTER)
180 STRINGIFY_CODE(TYPE_CODE, HALF)
181 STRINGIFY_CODE(TYPE_CODE, ARRAY)
182 STRINGIFY_CODE(TYPE_CODE, VECTOR)
183 STRINGIFY_CODE(TYPE_CODE, X86_FP80)
184 STRINGIFY_CODE(TYPE_CODE, FP128)
185 STRINGIFY_CODE(TYPE_CODE, PPC_FP128)
186 STRINGIFY_CODE(TYPE_CODE, METADATA)
187 STRINGIFY_CODE(TYPE_CODE, X86_MMX)
188 STRINGIFY_CODE(TYPE_CODE, STRUCT_ANON)
189 STRINGIFY_CODE(TYPE_CODE, STRUCT_NAME)
190 STRINGIFY_CODE(TYPE_CODE, STRUCT_NAMED)
191 STRINGIFY_CODE(TYPE_CODE, FUNCTION)
192 STRINGIFY_CODE(TYPE_CODE, TOKEN)
193 STRINGIFY_CODE(TYPE_CODE, BFLOAT)
194 }
195
196 case bitc::CONSTANTS_BLOCK_ID:
197 switch (CodeID) {
198 default:
199 return None;
200 STRINGIFY_CODE(CST_CODE, SETTYPE)
201 STRINGIFY_CODE(CST_CODE, NULL__null)
202 STRINGIFY_CODE(CST_CODE, UNDEF)
203 STRINGIFY_CODE(CST_CODE, INTEGER)
204 STRINGIFY_CODE(CST_CODE, WIDE_INTEGER)
205 STRINGIFY_CODE(CST_CODE, FLOAT)
206 STRINGIFY_CODE(CST_CODE, AGGREGATE)
207 STRINGIFY_CODE(CST_CODE, STRING)
208 STRINGIFY_CODE(CST_CODE, CSTRING)
209 STRINGIFY_CODE(CST_CODE, CE_BINOP)
210 STRINGIFY_CODE(CST_CODE, CE_CAST)
211 STRINGIFY_CODE(CST_CODE, CE_GEP)
212 STRINGIFY_CODE(CST_CODE, CE_INBOUNDS_GEP)
213 STRINGIFY_CODE(CST_CODE, CE_SELECT)
214 STRINGIFY_CODE(CST_CODE, CE_EXTRACTELT)
215 STRINGIFY_CODE(CST_CODE, CE_INSERTELT)
216 STRINGIFY_CODE(CST_CODE, CE_SHUFFLEVEC)
217 STRINGIFY_CODE(CST_CODE, CE_CMP)
218 STRINGIFY_CODE(CST_CODE, INLINEASM)
219 STRINGIFY_CODE(CST_CODE, CE_SHUFVEC_EX)
220 STRINGIFY_CODE(CST_CODE, CE_UNOP)
221 STRINGIFY_CODE(CST_CODE, DSO_LOCAL_EQUIVALENT)
222 case bitc::CST_CODE_BLOCKADDRESS:
223 return "CST_CODE_BLOCKADDRESS";
224 STRINGIFY_CODE(CST_CODE, DATA)
225 }
226 case bitc::FUNCTION_BLOCK_ID:
227 switch (CodeID) {
228 default:
229 return None;
230 STRINGIFY_CODE(FUNC_CODE, DECLAREBLOCKS)
231 STRINGIFY_CODE(FUNC_CODE, INST_BINOP)
232 STRINGIFY_CODE(FUNC_CODE, INST_CAST)
233 STRINGIFY_CODE(FUNC_CODE, INST_GEP_OLD)
234 STRINGIFY_CODE(FUNC_CODE, INST_INBOUNDS_GEP_OLD)
235 STRINGIFY_CODE(FUNC_CODE, INST_SELECT)
236 STRINGIFY_CODE(FUNC_CODE, INST_EXTRACTELT)
237 STRINGIFY_CODE(FUNC_CODE, INST_INSERTELT)
238 STRINGIFY_CODE(FUNC_CODE, INST_SHUFFLEVEC)
239 STRINGIFY_CODE(FUNC_CODE, INST_CMP)
240 STRINGIFY_CODE(FUNC_CODE, INST_RET)
241 STRINGIFY_CODE(FUNC_CODE, INST_BR)
242 STRINGIFY_CODE(FUNC_CODE, INST_SWITCH)
243 STRINGIFY_CODE(FUNC_CODE, INST_INVOKE)
244 STRINGIFY_CODE(FUNC_CODE, INST_UNOP)
245 STRINGIFY_CODE(FUNC_CODE, INST_UNREACHABLE)
246 STRINGIFY_CODE(FUNC_CODE, INST_CLEANUPRET)
247 STRINGIFY_CODE(FUNC_CODE, INST_CATCHRET)
248 STRINGIFY_CODE(FUNC_CODE, INST_CATCHPAD)
249 STRINGIFY_CODE(FUNC_CODE, INST_PHI)
250 STRINGIFY_CODE(FUNC_CODE, INST_ALLOCA)
251 STRINGIFY_CODE(FUNC_CODE, INST_LOAD)
252 STRINGIFY_CODE(FUNC_CODE, INST_VAARG)
253 STRINGIFY_CODE(FUNC_CODE, INST_STORE)
254 STRINGIFY_CODE(FUNC_CODE, INST_EXTRACTVAL)
255 STRINGIFY_CODE(FUNC_CODE, INST_INSERTVAL)
256 STRINGIFY_CODE(FUNC_CODE, INST_CMP2)
257 STRINGIFY_CODE(FUNC_CODE, INST_VSELECT)
258 STRINGIFY_CODE(FUNC_CODE, DEBUG_LOC_AGAIN)
259 STRINGIFY_CODE(FUNC_CODE, INST_CALL)
260 STRINGIFY_CODE(FUNC_CODE, DEBUG_LOC)
261 STRINGIFY_CODE(FUNC_CODE, INST_GEP)
262 STRINGIFY_CODE(FUNC_CODE, OPERAND_BUNDLE)
263 STRINGIFY_CODE(FUNC_CODE, INST_FENCE)
264 STRINGIFY_CODE(FUNC_CODE, INST_ATOMICRMW)
265 STRINGIFY_CODE(FUNC_CODE, INST_LOADATOMIC)
266 STRINGIFY_CODE(FUNC_CODE, INST_STOREATOMIC)
267 STRINGIFY_CODE(FUNC_CODE, INST_CMPXCHG)
268 STRINGIFY_CODE(FUNC_CODE, INST_CALLBR)
269 }
270 case bitc::VALUE_SYMTAB_BLOCK_ID:
271 switch (CodeID) {
272 default:
273 return None;
274 STRINGIFY_CODE(VST_CODE, ENTRY)
275 STRINGIFY_CODE(VST_CODE, BBENTRY)
276 STRINGIFY_CODE(VST_CODE, FNENTRY)
277 STRINGIFY_CODE(VST_CODE, COMBINED_ENTRY)
278 }
279 case bitc::MODULE_STRTAB_BLOCK_ID:
280 switch (CodeID) {
281 default:
282 return None;
283 STRINGIFY_CODE(MST_CODE, ENTRY)
284 STRINGIFY_CODE(MST_CODE, HASH)
285 }
286 case bitc::GLOBALVAL_SUMMARY_BLOCK_ID:
287 case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID:
288 switch (CodeID) {
289 default:
290 return None;
291 STRINGIFY_CODE(FS, PERMODULE)
292 STRINGIFY_CODE(FS, PERMODULE_PROFILE)
293 STRINGIFY_CODE(FS, PERMODULE_RELBF)
294 STRINGIFY_CODE(FS, PERMODULE_GLOBALVAR_INIT_REFS)
295 STRINGIFY_CODE(FS, PERMODULE_VTABLE_GLOBALVAR_INIT_REFS)
296 STRINGIFY_CODE(FS, COMBINED)
297 STRINGIFY_CODE(FS, COMBINED_PROFILE)
298 STRINGIFY_CODE(FS, COMBINED_GLOBALVAR_INIT_REFS)
299 STRINGIFY_CODE(FS, ALIAS)
300 STRINGIFY_CODE(FS, COMBINED_ALIAS)
301 STRINGIFY_CODE(FS, COMBINED_ORIGINAL_NAME)
302 STRINGIFY_CODE(FS, VERSION)
303 STRINGIFY_CODE(FS, FLAGS)
304 STRINGIFY_CODE(FS, TYPE_TESTS)
305 STRINGIFY_CODE(FS, TYPE_TEST_ASSUME_VCALLS)
306 STRINGIFY_CODE(FS, TYPE_CHECKED_LOAD_VCALLS)
307 STRINGIFY_CODE(FS, TYPE_TEST_ASSUME_CONST_VCALL)
308 STRINGIFY_CODE(FS, TYPE_CHECKED_LOAD_CONST_VCALL)
309 STRINGIFY_CODE(FS, VALUE_GUID)
310 STRINGIFY_CODE(FS, CFI_FUNCTION_DEFS)
311 STRINGIFY_CODE(FS, CFI_FUNCTION_DECLS)
312 STRINGIFY_CODE(FS, TYPE_ID)
313 STRINGIFY_CODE(FS, TYPE_ID_METADATA)
314 STRINGIFY_CODE(FS, BLOCK_COUNT)
315 STRINGIFY_CODE(FS, PARAM_ACCESS)
316 }
317 case bitc::METADATA_ATTACHMENT_ID:
318 switch (CodeID) {
319 default:
320 return None;
321 STRINGIFY_CODE(METADATA, ATTACHMENT)
322 }
323 case bitc::METADATA_BLOCK_ID:
324 switch (CodeID) {
325 default:
326 return None;
327 STRINGIFY_CODE(METADATA, STRING_OLD)
328 STRINGIFY_CODE(METADATA, VALUE)
329 STRINGIFY_CODE(METADATA, NODE)
330 STRINGIFY_CODE(METADATA, NAME)
331 STRINGIFY_CODE(METADATA, DISTINCT_NODE)
332 STRINGIFY_CODE(METADATA, KIND) // Older bitcode has it in a MODULE_BLOCK
333 STRINGIFY_CODE(METADATA, LOCATION)
334 STRINGIFY_CODE(METADATA, OLD_NODE)
335 STRINGIFY_CODE(METADATA, OLD_FN_NODE)
336 STRINGIFY_CODE(METADATA, NAMED_NODE)
337 STRINGIFY_CODE(METADATA, GENERIC_DEBUG)
338 STRINGIFY_CODE(METADATA, SUBRANGE)
339 STRINGIFY_CODE(METADATA, ENUMERATOR)
340 STRINGIFY_CODE(METADATA, BASIC_TYPE)
341 STRINGIFY_CODE(METADATA, FILE)
342 STRINGIFY_CODE(METADATA, DERIVED_TYPE)
343 STRINGIFY_CODE(METADATA, COMPOSITE_TYPE)
344 STRINGIFY_CODE(METADATA, SUBROUTINE_TYPE)
345 STRINGIFY_CODE(METADATA, COMPILE_UNIT)
346 STRINGIFY_CODE(METADATA, SUBPROGRAM)
347 STRINGIFY_CODE(METADATA, LEXICAL_BLOCK)
348 STRINGIFY_CODE(METADATA, LEXICAL_BLOCK_FILE)
349 STRINGIFY_CODE(METADATA, NAMESPACE)
350 STRINGIFY_CODE(METADATA, TEMPLATE_TYPE)
351 STRINGIFY_CODE(METADATA, TEMPLATE_VALUE)
352 STRINGIFY_CODE(METADATA, GLOBAL_VAR)
353 STRINGIFY_CODE(METADATA, LOCAL_VAR)
354 STRINGIFY_CODE(METADATA, EXPRESSION)
355 STRINGIFY_CODE(METADATA, OBJC_PROPERTY)
356 STRINGIFY_CODE(METADATA, IMPORTED_ENTITY)
357 STRINGIFY_CODE(METADATA, MODULE)
358 STRINGIFY_CODE(METADATA, MACRO)
359 STRINGIFY_CODE(METADATA, MACRO_FILE)
360 STRINGIFY_CODE(METADATA, STRINGS)
361 STRINGIFY_CODE(METADATA, GLOBAL_DECL_ATTACHMENT)
362 STRINGIFY_CODE(METADATA, GLOBAL_VAR_EXPR)
363 STRINGIFY_CODE(METADATA, INDEX_OFFSET)
364 STRINGIFY_CODE(METADATA, INDEX)
365 STRINGIFY_CODE(METADATA, ARG_LIST)
366 }
367 case bitc::METADATA_KIND_BLOCK_ID:
368 switch (CodeID) {
369 default:
370 return None;
371 STRINGIFY_CODE(METADATA, KIND)
372 }
373 case bitc::USELIST_BLOCK_ID:
374 switch (CodeID) {
375 default:
376 return None;
377 case bitc::USELIST_CODE_DEFAULT:
378 return "USELIST_CODE_DEFAULT";
379 case bitc::USELIST_CODE_BB:
380 return "USELIST_CODE_BB";
381 }
382
383 case bitc::OPERAND_BUNDLE_TAGS_BLOCK_ID:
384 switch (CodeID) {
385 default:
386 return None;
387 case bitc::OPERAND_BUNDLE_TAG:
388 return "OPERAND_BUNDLE_TAG";
389 }
390 case bitc::STRTAB_BLOCK_ID:
391 switch (CodeID) {
392 default:
393 return None;
394 case bitc::STRTAB_BLOB:
395 return "BLOB";
396 }
397 case bitc::SYMTAB_BLOCK_ID:
398 switch (CodeID) {
399 default:
400 return None;
401 case bitc::SYMTAB_BLOB:
402 return "BLOB";
403 }
404 }
405#undef STRINGIFY_CODE
406}
407
408static void printSize(raw_ostream &OS, double Bits) {
409 OS << format("%.2f/%.2fB/%luW", Bits, Bits / 8, (unsigned long)(Bits / 32));
410}
411static void printSize(raw_ostream &OS, uint64_t Bits) {
412 OS << format("%lub/%.2fB/%luW", (unsigned long)Bits, (double)Bits / 8,
413 (unsigned long)(Bits / 32));
414}
415
416static Expected<CurStreamTypeType> ReadSignature(BitstreamCursor &Stream) {
417 auto tryRead = [&Stream](char &Dest, size_t size) -> Error {
418 if (Expected<SimpleBitstreamCursor::word_t> MaybeWord = Stream.Read(size))
419 Dest = MaybeWord.get();
420 else
421 return MaybeWord.takeError();
422 return Error::success();
423 };
424
425 char Signature[6];
426 if (Error Err = tryRead(Signature[0], 8))
427 return std::move(Err);
428 if (Error Err = tryRead(Signature[1], 8))
429 return std::move(Err);
430
431 // Autodetect the file contents, if it is one we know.
432 if (Signature[0] == 'C' && Signature[1] == 'P') {
433 if (Error Err = tryRead(Signature[2], 8))
434 return std::move(Err);
435 if (Error Err = tryRead(Signature[3], 8))
436 return std::move(Err);
437 if (Signature[2] == 'C' && Signature[3] == 'H')
438 return ClangSerializedASTBitstream;
439 } else if (Signature[0] == 'D' && Signature[1] == 'I') {
440 if (Error Err = tryRead(Signature[2], 8))
441 return std::move(Err);
442 if (Error Err = tryRead(Signature[3], 8))
443 return std::move(Err);
444 if (Signature[2] == 'A' && Signature[3] == 'G')
445 return ClangSerializedDiagnosticsBitstream;
446 } else if (Signature[0] == 'R' && Signature[1] == 'M') {
447 if (Error Err = tryRead(Signature[2], 8))
448 return std::move(Err);
449 if (Error Err = tryRead(Signature[3], 8))
450 return std::move(Err);
451 if (Signature[2] == 'R' && Signature[3] == 'K')
452 return LLVMBitstreamRemarks;
453 } else {
454 if (Error Err = tryRead(Signature[2], 4))
455 return std::move(Err);
456 if (Error Err = tryRead(Signature[3], 4))
457 return std::move(Err);
458 if (Error Err = tryRead(Signature[4], 4))
459 return std::move(Err);
460 if (Error Err = tryRead(Signature[5], 4))
461 return std::move(Err);
462 if (Signature[0] == 'B' && Signature[1] == 'C' && Signature[2] == 0x0 &&
463 Signature[3] == 0xC && Signature[4] == 0xE && Signature[5] == 0xD)
464 return LLVMIRBitstream;
465 }
466 return UnknownBitstream;
467}
468
469static Expected<CurStreamTypeType> analyzeHeader(Optional<BCDumpOptions> O,
470 BitstreamCursor &Stream) {
471 ArrayRef<uint8_t> Bytes = Stream.getBitcodeBytes();
472 const unsigned char *BufPtr = (const unsigned char *)Bytes.data();
473 const unsigned char *EndBufPtr = BufPtr + Bytes.size();
474
475 // If we have a wrapper header, parse it and ignore the non-bc file
476 // contents. The magic number is 0x0B17C0DE stored in little endian.
477 if (isBitcodeWrapper(BufPtr, EndBufPtr)) {
478 if (Bytes.size() < BWH_HeaderSize)
479 return reportError("Invalid bitcode wrapper header");
480
481 if (O) {
482 unsigned Magic = support::endian::read32le(&BufPtr[BWH_MagicField]);
483 unsigned Version = support::endian::read32le(&BufPtr[BWH_VersionField]);
484 unsigned Offset = support::endian::read32le(&BufPtr[BWH_OffsetField]);
485 unsigned Size = support::endian::read32le(&BufPtr[BWH_SizeField]);
486 unsigned CPUType = support::endian::read32le(&BufPtr[BWH_CPUTypeField]);
487
488 O->OS << "<BITCODE_WRAPPER_HEADER"
489 << " Magic=" << format_hex(Magic, 10)
490 << " Version=" << format_hex(Version, 10)
491 << " Offset=" << format_hex(Offset, 10)
492 << " Size=" << format_hex(Size, 10)
493 << " CPUType=" << format_hex(CPUType, 10) << "/>\n";
494 }
495
496 if (SkipBitcodeWrapperHeader(BufPtr, EndBufPtr, true))
497 return reportError("Invalid bitcode wrapper header");
498 }
499
500 // Use the cursor modified by skipping the wrapper header.
501 Stream = BitstreamCursor(ArrayRef<uint8_t>(BufPtr, EndBufPtr));
502
503 return ReadSignature(Stream);
504}
505
506static bool canDecodeBlob(unsigned Code, unsigned BlockID) {
507 return BlockID == bitc::METADATA_BLOCK_ID && Code == bitc::METADATA_STRINGS;
508}
509
510Error BitcodeAnalyzer::decodeMetadataStringsBlob(StringRef Indent,
511 ArrayRef<uint64_t> Record,
512 StringRef Blob,
513 raw_ostream &OS) {
514 if (Blob.empty())
515 return reportError("Cannot decode empty blob.");
516
517 if (Record.size() != 2)
518 return reportError(
519 "Decoding metadata strings blob needs two record entries.");
520
521 unsigned NumStrings = Record[0];
522 unsigned StringsOffset = Record[1];
523 OS << " num-strings = " << NumStrings << " {\n";
524
525 StringRef Lengths = Blob.slice(0, StringsOffset);
526 SimpleBitstreamCursor R(Lengths);
527 StringRef Strings = Blob.drop_front(StringsOffset);
528 do {
529 if (R.AtEndOfStream())
530 return reportError("bad length");
531
532 Expected<uint32_t> MaybeSize = R.ReadVBR(6);
533 if (!MaybeSize)
534 return MaybeSize.takeError();
535 uint32_t Size = MaybeSize.get();
536 if (Strings.size() < Size)
537 return reportError("truncated chars");
538
539 OS << Indent << " '";
540 OS.write_escaped(Strings.slice(0, Size), /*hex=*/true);
541 OS << "'\n";
542 Strings = Strings.drop_front(Size);
543 } while (--NumStrings);
544
545 OS << Indent << " }";
546 return Error::success();
547}
548
549BitcodeAnalyzer::BitcodeAnalyzer(StringRef Buffer,
550 Optional<StringRef> BlockInfoBuffer)
551 : Stream(Buffer) {
552 if (BlockInfoBuffer)
553 BlockInfoStream.emplace(*BlockInfoBuffer);
554}
555
556Error BitcodeAnalyzer::analyze(Optional<BCDumpOptions> O,
557 Optional<StringRef> CheckHash) {
558 Expected<CurStreamTypeType> MaybeType = analyzeHeader(O, Stream);
559 if (!MaybeType)
560 return MaybeType.takeError();
561 else
562 CurStreamType = *MaybeType;
563
564 Stream.setBlockInfo(&BlockInfo);
565
566 // Read block info from BlockInfoStream, if specified.
567 // The block info must be a top-level block.
568 if (BlockInfoStream) {
569 BitstreamCursor BlockInfoCursor(*BlockInfoStream);
570 Expected<CurStreamTypeType> H = analyzeHeader(O, BlockInfoCursor);
571 if (!H)
572 return H.takeError();
573
574 while (!BlockInfoCursor.AtEndOfStream()) {
575 Expected<unsigned> MaybeCode = BlockInfoCursor.ReadCode();
576 if (!MaybeCode)
577 return MaybeCode.takeError();
578 if (MaybeCode.get() != bitc::ENTER_SUBBLOCK)
579 return reportError("Invalid record at top-level in block info file");
580
581 Expected<unsigned> MaybeBlockID = BlockInfoCursor.ReadSubBlockID();
582 if (!MaybeBlockID)
583 return MaybeBlockID.takeError();
584 if (MaybeBlockID.get() == bitc::BLOCKINFO_BLOCK_ID) {
585 Expected<Optional<BitstreamBlockInfo>> MaybeNewBlockInfo =
586 BlockInfoCursor.ReadBlockInfoBlock(/*ReadBlockInfoNames=*/true);
587 if (!MaybeNewBlockInfo)
588 return MaybeNewBlockInfo.takeError();
589 Optional<BitstreamBlockInfo> NewBlockInfo =
590 std::move(MaybeNewBlockInfo.get());
591 if (!NewBlockInfo)
592 return reportError("Malformed BlockInfoBlock in block info file");
593 BlockInfo = std::move(*NewBlockInfo);
594 break;
595 }
596
597 if (Error Err = BlockInfoCursor.SkipBlock())
598 return Err;
599 }
600 }
601
602 // Parse the top-level structure. We only allow blocks at the top-level.
603 while (!Stream.AtEndOfStream()) {
604 Expected<unsigned> MaybeCode = Stream.ReadCode();
605 if (!MaybeCode)
606 return MaybeCode.takeError();
607 if (MaybeCode.get() != bitc::ENTER_SUBBLOCK)
608 return reportError("Invalid record at top-level");
609
610 Expected<unsigned> MaybeBlockID = Stream.ReadSubBlockID();
611 if (!MaybeBlockID)
612 return MaybeBlockID.takeError();
613
614 if (Error E = parseBlock(MaybeBlockID.get(), 0, O, CheckHash))
615 return E;
616 ++NumTopBlocks;
617 }
618
619 return Error::success();
620}
621
622void BitcodeAnalyzer::printStats(BCDumpOptions O,
623 Optional<StringRef> Filename) {
624 uint64_t BufferSizeBits = Stream.getBitcodeBytes().size() * CHAR_BIT8;
625 // Print a summary of the read file.
626 O.OS << "Summary ";
627 if (Filename)
628 O.OS << "of " << Filename->data() << ":\n";
629 O.OS << " Total size: ";
630 printSize(O.OS, BufferSizeBits);
631 O.OS << "\n";
632 O.OS << " Stream type: ";
633 switch (CurStreamType) {
634 case UnknownBitstream:
635 O.OS << "unknown\n";
636 break;
637 case LLVMIRBitstream:
638 O.OS << "LLVM IR\n";
639 break;
640 case ClangSerializedASTBitstream:
641 O.OS << "Clang Serialized AST\n";
642 break;
643 case ClangSerializedDiagnosticsBitstream:
644 O.OS << "Clang Serialized Diagnostics\n";
645 break;
646 case LLVMBitstreamRemarks:
647 O.OS << "LLVM Remarks\n";
648 break;
649 }
650 O.OS << " # Toplevel Blocks: " << NumTopBlocks << "\n";
651 O.OS << "\n";
652
653 // Emit per-block stats.
654 O.OS << "Per-block Summary:\n";
655 for (std::map<unsigned, PerBlockIDStats>::iterator I = BlockIDStats.begin(),
656 E = BlockIDStats.end();
657 I != E; ++I) {
658 O.OS << " Block ID #" << I->first;
659 if (Optional<const char *> BlockName =
660 GetBlockName(I->first, BlockInfo, CurStreamType))
661 O.OS << " (" << *BlockName << ")";
662 O.OS << ":\n";
663
664 const PerBlockIDStats &Stats = I->second;
665 O.OS << " Num Instances: " << Stats.NumInstances << "\n";
666 O.OS << " Total Size: ";
667 printSize(O.OS, Stats.NumBits);
668 O.OS << "\n";
669 double pct = (Stats.NumBits * 100.0) / BufferSizeBits;
670 O.OS << " Percent of file: " << format("%2.4f%%", pct) << "\n";
671 if (Stats.NumInstances > 1) {
672 O.OS << " Average Size: ";
673 printSize(O.OS, Stats.NumBits / (double)Stats.NumInstances);
674 O.OS << "\n";
675 O.OS << " Tot/Avg SubBlocks: " << Stats.NumSubBlocks << "/"
676 << Stats.NumSubBlocks / (double)Stats.NumInstances << "\n";
677 O.OS << " Tot/Avg Abbrevs: " << Stats.NumAbbrevs << "/"
678 << Stats.NumAbbrevs / (double)Stats.NumInstances << "\n";
679 O.OS << " Tot/Avg Records: " << Stats.NumRecords << "/"
680 << Stats.NumRecords / (double)Stats.NumInstances << "\n";
681 } else {
682 O.OS << " Num SubBlocks: " << Stats.NumSubBlocks << "\n";
683 O.OS << " Num Abbrevs: " << Stats.NumAbbrevs << "\n";
684 O.OS << " Num Records: " << Stats.NumRecords << "\n";
685 }
686 if (Stats.NumRecords) {
687 double pct = (Stats.NumAbbreviatedRecords * 100.0) / Stats.NumRecords;
688 O.OS << " Percent Abbrevs: " << format("%2.4f%%", pct) << "\n";
689 }
690 O.OS << "\n";
691
692 // Print a histogram of the codes we see.
693 if (O.Histogram && !Stats.CodeFreq.empty()) {
694 std::vector<std::pair<unsigned, unsigned>> FreqPairs; // <freq,code>
695 for (unsigned i = 0, e = Stats.CodeFreq.size(); i != e; ++i)
696 if (unsigned Freq = Stats.CodeFreq[i].NumInstances)
697 FreqPairs.push_back(std::make_pair(Freq, i));
698 llvm::stable_sort(FreqPairs);
699 std::reverse(FreqPairs.begin(), FreqPairs.end());
700
701 O.OS << "\tRecord Histogram:\n";
702 O.OS << "\t\t Count # Bits b/Rec % Abv Record Kind\n";
703 for (unsigned i = 0, e = FreqPairs.size(); i != e; ++i) {
704 const PerRecordStats &RecStats = Stats.CodeFreq[FreqPairs[i].second];
705
706 O.OS << format("\t\t%7d %9lu", RecStats.NumInstances,
707 (unsigned long)RecStats.TotalBits);
708
709 if (RecStats.NumInstances > 1)
710 O.OS << format(" %9.1f",
711 (double)RecStats.TotalBits / RecStats.NumInstances);
712 else
713 O.OS << " ";
714
715 if (RecStats.NumAbbrev)
716 O.OS << format(" %7.2f", (double)RecStats.NumAbbrev /
717 RecStats.NumInstances * 100);
718 else
719 O.OS << " ";
720
721 O.OS << " ";
722 if (Optional<const char *> CodeName = GetCodeName(
723 FreqPairs[i].second, I->first, BlockInfo, CurStreamType))
724 O.OS << *CodeName << "\n";
725 else
726 O.OS << "UnknownCode" << FreqPairs[i].second << "\n";
727 }
728 O.OS << "\n";
729 }
730 }
731}
732
733Error BitcodeAnalyzer::parseBlock(unsigned BlockID, unsigned IndentLevel,
734 Optional<BCDumpOptions> O,
735 Optional<StringRef> CheckHash) {
736 std::string Indent(IndentLevel * 2, ' ');
737 uint64_t BlockBitStart = Stream.GetCurrentBitNo();
738
739 // Get the statistics for this BlockID.
740 PerBlockIDStats &BlockStats = BlockIDStats[BlockID];
741
742 BlockStats.NumInstances++;
743
744 // BLOCKINFO is a special part of the stream.
745 bool DumpRecords = O.hasValue();
746 if (BlockID == bitc::BLOCKINFO_BLOCK_ID) {
1
Assuming 'BlockID' is not equal to BLOCKINFO_BLOCK_ID
→
2
←
Taking false branch
→
747 if (O)
748 O->OS << Indent << "<BLOCKINFO_BLOCK/>\n";
749 Expected<Optional<BitstreamBlockInfo>> MaybeNewBlockInfo =
750 Stream.ReadBlockInfoBlock(/*ReadBlockInfoNames=*/true);
751 if (!MaybeNewBlockInfo)
752 return MaybeNewBlockInfo.takeError();
753 Optional<BitstreamBlockInfo> NewBlockInfo =
754 std::move(MaybeNewBlockInfo.get());
755 if (!NewBlockInfo)
756 return reportError("Malformed BlockInfoBlock");
757 BlockInfo = std::move(*NewBlockInfo);
758 if (Error Err = Stream.JumpToBit(BlockBitStart))
759 return Err;
760 // It's not really interesting to dump the contents of the blockinfo
761 // block.
762 DumpRecords = false;
763 }
764
765 unsigned NumWords = 0;
766 if (Error Err = Stream.EnterSubBlock(BlockID, &NumWords))
3
←
Assuming the condition is false
→
4
←
Taking false branch
→
767 return Err;
768
769 // Keep it for later, when we see a MODULE_HASH record
770 uint64_t BlockEntryPos = Stream.getCurrentByteNo();
771
772 Optional<const char *> BlockName = None;
773 if (DumpRecords) {
5
←
Assuming 'DumpRecords' is false
→
6
←
Taking false branch
→
774 O->OS << Indent << "<";
775 if ((BlockName = GetBlockName(BlockID, BlockInfo, CurStreamType)))
776 O->OS << *BlockName;
777 else
778 O->OS << "UnknownBlock" << BlockID;
779
780 if (!O->Symbolic && BlockName)
781 O->OS << " BlockID=" << BlockID;
782
783 O->OS << " NumWords=" << NumWords
784 << " BlockCodeSize=" << Stream.getAbbrevIDWidth() << ">\n";
785 }
786
787 SmallVector<uint64_t, 64> Record;
788
789 // Keep the offset to the metadata index if seen.
790 uint64_t MetadataIndexOffset = 0;
791
792 // Read all the records for this block.
793 while (1) {
7
←
Loop condition is true. Entering loop body
→
794 if (Stream.AtEndOfStream())
8
←
Taking false branch
→
795 return reportError("Premature end of bitstream");
796
797 uint64_t RecordStartBit = Stream.GetCurrentBitNo();
798
799 Expected<BitstreamEntry> MaybeEntry =
800 Stream.advance(BitstreamCursor::AF_DontAutoprocessAbbrevs);
9
←
Calling 'BitstreamCursor::advance'
→
801 if (!MaybeEntry)
802 return MaybeEntry.takeError();
803 BitstreamEntry Entry = MaybeEntry.get();
804
805 switch (Entry.Kind) {
806 case BitstreamEntry::Error:
807 return reportError("malformed bitcode file");
808 case BitstreamEntry::EndBlock: {
809 uint64_t BlockBitEnd = Stream.GetCurrentBitNo();
810 BlockStats.NumBits += BlockBitEnd - BlockBitStart;
811 if (DumpRecords) {
812 O->OS << Indent << "</";
813 if (BlockName)
814 O->OS << *BlockName << ">\n";
815 else
816 O->OS << "UnknownBlock" << BlockID << ">\n";
817 }
818 return Error::success();
819 }
820
821 case BitstreamEntry::SubBlock: {
822 uint64_t SubBlockBitStart = Stream.GetCurrentBitNo();
823 if (Error E = parseBlock(Entry.ID, IndentLevel + 1, O, CheckHash))
824 return E;
825 ++BlockStats.NumSubBlocks;
826 uint64_t SubBlockBitEnd = Stream.GetCurrentBitNo();
827
828 // Don't include subblock sizes in the size of this block.
829 BlockBitStart += SubBlockBitEnd - SubBlockBitStart;
830 continue;
831 }
832 case BitstreamEntry::Record:
833 // The interesting case.
834 break;
835 }
836
837 if (Entry.ID == bitc::DEFINE_ABBREV) {
838 if (Error Err = Stream.ReadAbbrevRecord())
839 return Err;
840 ++BlockStats.NumAbbrevs;
841 continue;
842 }
843
844 Record.clear();
845
846 ++BlockStats.NumRecords;
847
848 StringRef Blob;
849 uint64_t CurrentRecordPos = Stream.GetCurrentBitNo();
850 Expected<unsigned> MaybeCode = Stream.readRecord(Entry.ID, Record, &Blob);
851 if (!MaybeCode)
852 return MaybeCode.takeError();
853 unsigned Code = MaybeCode.get();
854
855 // Increment the # occurrences of this code.
856 if (BlockStats.CodeFreq.size() <= Code)
857 BlockStats.CodeFreq.resize(Code + 1);
858 BlockStats.CodeFreq[Code].NumInstances++;
859 BlockStats.CodeFreq[Code].TotalBits +=
860 Stream.GetCurrentBitNo() - RecordStartBit;
861 if (Entry.ID != bitc::UNABBREV_RECORD) {
862 BlockStats.CodeFreq[Code].NumAbbrev++;
863 ++BlockStats.NumAbbreviatedRecords;
864 }
865
866 if (DumpRecords) {
867 O->OS << Indent << " <";
868 Optional<const char *> CodeName =
869 GetCodeName(Code, BlockID, BlockInfo, CurStreamType);
870 if (CodeName)
871 O->OS << *CodeName;
872 else
873 O->OS << "UnknownCode" << Code;
874 if (!O->Symbolic && CodeName)
875 O->OS << " codeid=" << Code;
876 const BitCodeAbbrev *Abbv = nullptr;
877 if (Entry.ID != bitc::UNABBREV_RECORD) {
878 Abbv = Stream.getAbbrev(Entry.ID);
879 O->OS << " abbrevid=" << Entry.ID;
880 }
881
882 for (unsigned i = 0, e = Record.size(); i != e; ++i)
883 O->OS << " op" << i << "=" << (int64_t)Record[i];
884
885 // If we found a metadata index, let's verify that we had an offset
886 // before and validate its forward reference offset was correct!
887 if (BlockID == bitc::METADATA_BLOCK_ID) {
888 if (Code == bitc::METADATA_INDEX_OFFSET) {
889 if (Record.size() != 2)
890 O->OS << "(Invalid record)";
891 else {
892 auto Offset = Record[0] + (Record[1] << 32);
893 MetadataIndexOffset = Stream.GetCurrentBitNo() + Offset;
894 }
895 }
896 if (Code == bitc::METADATA_INDEX) {
897 O->OS << " (offset ";
898 if (MetadataIndexOffset == RecordStartBit)
899 O->OS << "match)";
900 else
901 O->OS << "mismatch: " << MetadataIndexOffset << " vs "
902 << RecordStartBit << ")";
903 }
904 }
905
906 // If we found a module hash, let's verify that it matches!
907 if (BlockID == bitc::MODULE_BLOCK_ID && Code == bitc::MODULE_CODE_HASH &&
908 CheckHash.hasValue()) {
909 if (Record.size() != 5)
910 O->OS << " (invalid)";
911 else {
912 // Recompute the hash and compare it to the one in the bitcode
913 SHA1 Hasher;
914 StringRef Hash;
915 Hasher.update(*CheckHash);
916 {
917 int BlockSize = (CurrentRecordPos / 8) - BlockEntryPos;
918 auto Ptr = Stream.getPointerToByte(BlockEntryPos, BlockSize);
919 Hasher.update(ArrayRef<uint8_t>(Ptr, BlockSize));
920 Hash = Hasher.result();
921 }
922 std::array<char, 20> RecordedHash;
923 int Pos = 0;
924 for (auto &Val : Record) {
925 assert(!(Val >> 32) && "Unexpected high bits set")(static_cast <bool> (!(Val >> 32) && "Unexpected high bits set"
) ? void (0) : __assert_fail ("!(Val >> 32) && \"Unexpected high bits set\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp"
, 925, __extension__ __PRETTY_FUNCTION__));
926 support::endian::write32be(&RecordedHash[Pos], Val);
927 Pos += 4;
928 }
929 if (Hash == StringRef(RecordedHash.data(), RecordedHash.size()))
930 O->OS << " (match)";
931 else
932 O->OS << " (!mismatch!)";
933 }
934 }
935
936 O->OS << "/>";
937
938 if (Abbv) {
939 for (unsigned i = 1, e = Abbv->getNumOperandInfos(); i != e; ++i) {
940 const BitCodeAbbrevOp &Op = Abbv->getOperandInfo(i);
941 if (!Op.isEncoding() || Op.getEncoding() != BitCodeAbbrevOp::Array)
942 continue;
943 assert(i + 2 == e && "Array op not second to last")(static_cast <bool> (i + 2 == e && "Array op not second to last"
) ? void (0) : __assert_fail ("i + 2 == e && \"Array op not second to last\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp"
, 943, __extension__ __PRETTY_FUNCTION__));
944 std::string Str;
945 bool ArrayIsPrintable = true;
946 for (unsigned j = i - 1, je = Record.size(); j != je; ++j) {
947 if (!isPrint(static_cast<unsigned char>(Record[j]))) {
948 ArrayIsPrintable = false;
949 break;
950 }
951 Str += (char)Record[j];
952 }
953 if (ArrayIsPrintable)
954 O->OS << " record string = '" << Str << "'";
955 break;
956 }
957 }
958
959 if (Blob.data()) {
960 if (canDecodeBlob(Code, BlockID)) {
961 if (Error E = decodeMetadataStringsBlob(Indent, Record, Blob, O->OS))
962 return E;
963 } else {
964 O->OS << " blob data = ";
965 if (O->ShowBinaryBlobs) {
966 O->OS << "'";
967 O->OS.write_escaped(Blob, /*hex=*/true) << "'";
968 } else {
969 bool BlobIsPrintable = true;
970 for (unsigned i = 0, e = Blob.size(); i != e; ++i)
971 if (!isPrint(static_cast<unsigned char>(Blob[i]))) {
972 BlobIsPrintable = false;
973 break;
974 }
975
976 if (BlobIsPrintable)
977 O->OS << "'" << Blob << "'";
978 else
979 O->OS << "unprintable, " << Blob.size() << " bytes.";
980 }
981 }
982 }
983
984 O->OS << "\n";
985 }
986
987 // Make sure that we can skip the current record.
988 if (Error Err = Stream.JumpToBit(CurrentRecordPos))
989 return Err;
990 if (Expected<unsigned> Skipped = Stream.skipRecord(Entry.ID))
991 ; // Do nothing.
992 else
993 return Skipped.takeError();
994 }
995}
996
←

/usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/basic_string.h

→
1// Components for manipulating sequences of characters -*- C++ -*-
2
3// Copyright (C) 1997-2020 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file bits/basic_string.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly. @headername{string}
28 */
29
30//
31// ISO C++ 14882: 21 Strings library
32//
33
34#ifndef _BASIC_STRING_H1
35#define _BASIC_STRING_H1 1
36
37#pragma GCC system_header
38
39#include <ext/atomicity.h>
40#include <ext/alloc_traits.h>
41#include <debug/debug.h>
42
43#if __cplusplus201402L >= 201103L
44#include <initializer_list>
45#endif
46
47#if __cplusplus201402L >= 201703L
48# include <string_view>
49#endif
50
51
52namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
53{
54_GLIBCXX_BEGIN_NAMESPACE_VERSION
55
56#if _GLIBCXX_USE_CXX11_ABI1
57_GLIBCXX_BEGIN_NAMESPACE_CXX11namespace __cxx11 {
58 /**
59 * @class basic_string basic_string.h <string>
60 * @brief Managing sequences of characters and character-like objects.
61 *
62 * @ingroup strings
63 * @ingroup sequences
64 *
65 * @tparam _CharT Type of character
66 * @tparam _Traits Traits for character type, defaults to
67 * char_traits<_CharT>.
68 * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
69 *
70 * Meets the requirements of a <a href="tables.html#65">container</a>, a
71 * <a href="tables.html#66">reversible container</a>, and a
72 * <a href="tables.html#67">sequence</a>. Of the
73 * <a href="tables.html#68">optional sequence requirements</a>, only
74 * @c push_back, @c at, and @c %array access are supported.
75 */
76 template<typename _CharT, typename _Traits, typename _Alloc>
77 class basic_string
78 {
79 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
80 rebind<_CharT>::other _Char_alloc_type;
81 typedef __gnu_cxx::__alloc_traits<_Char_alloc_type> _Alloc_traits;
82
83 // Types:
84 public:
85 typedef _Traits traits_type;
86 typedef typename _Traits::char_type value_type;
87 typedef _Char_alloc_type allocator_type;
88 typedef typename _Alloc_traits::size_type size_type;
89 typedef typename _Alloc_traits::difference_type difference_type;
90 typedef typename _Alloc_traits::reference reference;
91 typedef typename _Alloc_traits::const_reference const_reference;
92 typedef typename _Alloc_traits::pointer pointer;
93 typedef typename _Alloc_traits::const_pointer const_pointer;
94 typedef __gnu_cxx::__normal_iterator<pointer, basic_string> iterator;
95 typedef __gnu_cxx::__normal_iterator<const_pointer, basic_string>
96 const_iterator;
97 typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
98 typedef std::reverse_iterator<iterator> reverse_iterator;
99
100 /// Value returned by various member functions when they fail.
101 static const size_type npos = static_cast<size_type>(-1);
102
103 protected:
104 // type used for positions in insert, erase etc.
105#if __cplusplus201402L < 201103L
106 typedef iterator __const_iterator;
107#else
108 typedef const_iterator __const_iterator;
109#endif
110
111 private:
112#if __cplusplus201402L >= 201703L
113 // A helper type for avoiding boiler-plate.
114 typedef basic_string_view<_CharT, _Traits> __sv_type;
115
116 template<typename _Tp, typename _Res>
117 using _If_sv = enable_if_t<
118 __and_<is_convertible<const _Tp&, __sv_type>,
119 __not_<is_convertible<const _Tp*, const basic_string*>>,
120 __not_<is_convertible<const _Tp&, const _CharT*>>>::value,
121 _Res>;
122
123 // Allows an implicit conversion to __sv_type.
124 static __sv_type
125 _S_to_string_view(__sv_type __svt) noexcept
126 { return __svt; }
127
128 // Wraps a string_view by explicit conversion and thus
129 // allows to add an internal constructor that does not
130 // participate in overload resolution when a string_view
131 // is provided.
132 struct __sv_wrapper
133 {
134 explicit __sv_wrapper(__sv_type __sv) noexcept : _M_sv(__sv) { }
135 __sv_type _M_sv;
136 };
137
138 /**
139 * @brief Only internally used: Construct string from a string view
140 * wrapper.
141 * @param __svw string view wrapper.
142 * @param __a Allocator to use.
143 */
144 explicit
145 basic_string(__sv_wrapper __svw, const _Alloc& __a)
146 : basic_string(__svw._M_sv.data(), __svw._M_sv.size(), __a) { }
147#endif
148
149 // Use empty-base optimization: http://www.cantrip.org/emptyopt.html
150 struct _Alloc_hider : allocator_type // TODO check __is_final
151 {
152#if __cplusplus201402L < 201103L
153 _Alloc_hider(pointer __dat, const _Alloc& __a = _Alloc())
154 : allocator_type(__a), _M_p(__dat) { }
155#else
156 _Alloc_hider(pointer __dat, const _Alloc& __a)
157 : allocator_type(__a), _M_p(__dat) { }
158
159 _Alloc_hider(pointer __dat, _Alloc&& __a = _Alloc())
160 : allocator_type(std::move(__a)), _M_p(__dat) { }
161#endif
162
163 pointer _M_p; // The actual data.
164 };
165
166 _Alloc_hider _M_dataplus;
167 size_type _M_string_length;
168
169 enum { _S_local_capacity = 15 / sizeof(_CharT) };
170
171 union
172 {
173 _CharT _M_local_buf[_S_local_capacity + 1];
174 size_type _M_allocated_capacity;
175 };
176
177 void
178 _M_data(pointer __p)
179 { _M_dataplus._M_p = __p; }
180
181 void
182 _M_length(size_type __length)
183 { _M_string_length = __length; }
184
185 pointer
186 _M_data() const
187 { return _M_dataplus._M_p; }
188
189 pointer
190 _M_local_data()
191 {
192#if __cplusplus201402L >= 201103L
193 return std::pointer_traits<pointer>::pointer_to(*_M_local_buf);
194#else
195 return pointer(_M_local_buf);
196#endif
197 }
198
199 const_pointer
200 _M_local_data() const
201 {
202#if __cplusplus201402L >= 201103L
203 return std::pointer_traits<const_pointer>::pointer_to(*_M_local_buf);
204#else
205 return const_pointer(_M_local_buf);
206#endif
207 }
208
209 void
210 _M_capacity(size_type __capacity)
211 { _M_allocated_capacity = __capacity; }
212
213 void
214 _M_set_length(size_type __n)
215 {
216 _M_length(__n);
217 traits_type::assign(_M_data()[__n], _CharT());
218 }
219
220 bool
221 _M_is_local() const
222 { return _M_data() == _M_local_data(); }
223
224 // Create & Destroy
225 pointer
226 _M_create(size_type&, size_type);
227
228 void
229 _M_dispose()
230 {
231 if (!_M_is_local())
232 _M_destroy(_M_allocated_capacity);
233 }
234
235 void
236 _M_destroy(size_type __size) throw()
237 { _Alloc_traits::deallocate(_M_get_allocator(), _M_data(), __size + 1); }
238
239 // _M_construct_aux is used to implement the 21.3.1 para 15 which
240 // requires special behaviour if _InIterator is an integral type
241 template<typename _InIterator>
242 void
243 _M_construct_aux(_InIterator __beg, _InIterator __end,
244 std::__false_type)
245 {
246 typedef typename iterator_traits<_InIterator>::iterator_category _Tag;
247 _M_construct(__beg, __end, _Tag());
248 }
249
250 // _GLIBCXX_RESOLVE_LIB_DEFECTS
251 // 438. Ambiguity in the "do the right thing" clause
252 template<typename _Integer>
253 void
254 _M_construct_aux(_Integer __beg, _Integer __end, std::__true_type)
255 { _M_construct_aux_2(static_cast<size_type>(__beg), __end); }
256
257 void
258 _M_construct_aux_2(size_type __req, _CharT __c)
259 { _M_construct(__req, __c); }
260
261 template<typename _InIterator>
262 void
263 _M_construct(_InIterator __beg, _InIterator __end)
264 {
265 typedef typename std::__is_integer<_InIterator>::__type _Integral;
266 _M_construct_aux(__beg, __end, _Integral());
267 }
268
269 // For Input Iterators, used in istreambuf_iterators, etc.
270 template<typename _InIterator>
271 void
272 _M_construct(_InIterator __beg, _InIterator __end,
273 std::input_iterator_tag);
274
275 // For forward_iterators up to random_access_iterators, used for
276 // string::iterator, _CharT*, etc.
277 template<typename _FwdIterator>
278 void
279 _M_construct(_FwdIterator __beg, _FwdIterator __end,
280 std::forward_iterator_tag);
281
282 void
283 _M_construct(size_type __req, _CharT __c);
284
285 allocator_type&
286 _M_get_allocator()
287 { return _M_dataplus; }
288
289 const allocator_type&
290 _M_get_allocator() const
291 { return _M_dataplus; }
292
293 private:
294
295#ifdef _GLIBCXX_DISAMBIGUATE_REPLACE_INST
296 // The explicit instantiations in misc-inst.cc require this due to
297 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64063
298 template<typename _Tp, bool _Requires =
299 !__are_same<_Tp, _CharT*>::__value
300 && !__are_same<_Tp, const _CharT*>::__value
301 && !__are_same<_Tp, iterator>::__value
302 && !__are_same<_Tp, const_iterator>::__value>
303 struct __enable_if_not_native_iterator
304 { typedef basic_string& __type; };
305 template<typename _Tp>
306 struct __enable_if_not_native_iterator<_Tp, false> { };
307#endif
308
309 size_type
310 _M_check(size_type __pos, const char* __s) const
311 {
312 if (__pos > this->size())
313 __throw_out_of_range_fmt(__N("%s: __pos (which is %zu) > "("%s: __pos (which is %zu) > " "this->size() (which is %zu)"
)
314 "this->size() (which is %zu)")("%s: __pos (which is %zu) > " "this->size() (which is %zu)"
),
315 __s, __pos, this->size());
316 return __pos;
317 }
318
319 void
320 _M_check_length(size_type __n1, size_type __n2, const char* __s) const
321 {
322 if (this->max_size() - (this->size() - __n1) < __n2)
323 __throw_length_error(__N(__s)(__s));
324 }
325
326
327 // NB: _M_limit doesn't check for a bad __pos value.
328 size_type
329 _M_limit(size_type __pos, size_type __off) const _GLIBCXX_NOEXCEPTnoexcept
330 {
331 const bool __testoff = __off < this->size() - __pos;
332 return __testoff ? __off : this->size() - __pos;
333 }
334
335 // True if _Rep and source do not overlap.
336 bool
337 _M_disjunct(const _CharT* __s) const _GLIBCXX_NOEXCEPTnoexcept
338 {
339 return (less<const _CharT*>()(__s, _M_data())
340 || less<const _CharT*>()(_M_data() + this->size(), __s));
341 }
342
343 // When __n = 1 way faster than the general multichar
344 // traits_type::copy/move/assign.
345 static void
346 _S_copy(_CharT* __d, const _CharT* __s, size_type __n)
347 {
348 if (__n == 1)
349 traits_type::assign(*__d, *__s);
350 else
351 traits_type::copy(__d, __s, __n);
352 }
353
354 static void
355 _S_move(_CharT* __d, const _CharT* __s, size_type __n)
356 {
357 if (__n == 1)
358 traits_type::assign(*__d, *__s);
359 else
360 traits_type::move(__d, __s, __n);
361 }
362
363 static void
364 _S_assign(_CharT* __d, size_type __n, _CharT __c)
365 {
366 if (__n == 1)
367 traits_type::assign(*__d, __c);
368 else
369 traits_type::assign(__d, __n, __c);
370 }
371
372 // _S_copy_chars is a separate template to permit specialization
373 // to optimize for the common case of pointers as iterators.
374 template<class _Iterator>
375 static void
376 _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
377 {
378 for (; __k1 != __k2; ++__k1, (void)++__p)
379 traits_type::assign(*__p, *__k1); // These types are off.
380 }
381
382 static void
383 _S_copy_chars(_CharT* __p, iterator __k1, iterator __k2) _GLIBCXX_NOEXCEPTnoexcept
384 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
385
386 static void
387 _S_copy_chars(_CharT* __p, const_iterator __k1, const_iterator __k2)
388 _GLIBCXX_NOEXCEPTnoexcept
389 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
390
391 static void
392 _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2) _GLIBCXX_NOEXCEPTnoexcept
393 { _S_copy(__p, __k1, __k2 - __k1); }
394
395 static void
396 _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
397 _GLIBCXX_NOEXCEPTnoexcept
398 { _S_copy(__p, __k1, __k2 - __k1); }
399
400 static int
401 _S_compare(size_type __n1, size_type __n2) _GLIBCXX_NOEXCEPTnoexcept
402 {
403 const difference_type __d = difference_type(__n1 - __n2);
404
405 if (__d > __gnu_cxx::__numeric_traits<int>::__max)
406 return __gnu_cxx::__numeric_traits<int>::__max;
407 else if (__d < __gnu_cxx::__numeric_traits<int>::__min)
408 return __gnu_cxx::__numeric_traits<int>::__min;
409 else
410 return int(__d);
411 }
412
413 void
414 _M_assign(const basic_string&);
415
416 void
417 _M_mutate(size_type __pos, size_type __len1, const _CharT* __s,
418 size_type __len2);
419
420 void
421 _M_erase(size_type __pos, size_type __n);
422
423 public:
424 // Construct/copy/destroy:
425 // NB: We overload ctors in some cases instead of using default
426 // arguments, per 17.4.4.4 para. 2 item 2.
427
428 /**
429 * @brief Default constructor creates an empty string.
430 */
431 basic_string()
432 _GLIBCXX_NOEXCEPT_IF(is_nothrow_default_constructible<_Alloc>::value)noexcept(is_nothrow_default_constructible<_Alloc>::value
)
433 : _M_dataplus(_M_local_data())
434 { _M_set_length(0); }
435
436 /**
437 * @brief Construct an empty string using allocator @a a.
438 */
439 explicit
440 basic_string(const _Alloc& __a) _GLIBCXX_NOEXCEPTnoexcept
441 : _M_dataplus(_M_local_data(), __a)
442 { _M_set_length(0); }
443
444 /**
445 * @brief Construct string with copy of value of @a __str.
446 * @param __str Source string.
447 */
448 basic_string(const basic_string& __str)
449 : _M_dataplus(_M_local_data(),
450 _Alloc_traits::_S_select_on_copy(__str._M_get_allocator()))
451 { _M_construct(__str._M_data(), __str._M_data() + __str.length()); }
452
453 // _GLIBCXX_RESOLVE_LIB_DEFECTS
454 // 2583. no way to supply an allocator for basic_string(str, pos)
455 /**
456 * @brief Construct string as copy of a substring.
457 * @param __str Source string.
458 * @param __pos Index of first character to copy from.
459 * @param __a Allocator to use.
460 */
461 basic_string(const basic_string& __str, size_type __pos,
462 const _Alloc& __a = _Alloc())
463 : _M_dataplus(_M_local_data(), __a)
464 {
465 const _CharT* __start = __str._M_data()
466 + __str._M_check(__pos, "basic_string::basic_string");
467 _M_construct(__start, __start + __str._M_limit(__pos, npos));
468 }
469
470 /**
471 * @brief Construct string as copy of a substring.
472 * @param __str Source string.
473 * @param __pos Index of first character to copy from.
474 * @param __n Number of characters to copy.
475 */
476 basic_string(const basic_string& __str, size_type __pos,
477 size_type __n)
478 : _M_dataplus(_M_local_data())
479 {
480 const _CharT* __start = __str._M_data()
481 + __str._M_check(__pos, "basic_string::basic_string");
482 _M_construct(__start, __start + __str._M_limit(__pos, __n));
483 }
484
485 /**
486 * @brief Construct string as copy of a substring.
487 * @param __str Source string.
488 * @param __pos Index of first character to copy from.
489 * @param __n Number of characters to copy.
490 * @param __a Allocator to use.
491 */
492 basic_string(const basic_string& __str, size_type __pos,
493 size_type __n, const _Alloc& __a)
494 : _M_dataplus(_M_local_data(), __a)
495 {
496 const _CharT* __start
497 = __str._M_data() + __str._M_check(__pos, "string::string");
498 _M_construct(__start, __start + __str._M_limit(__pos, __n));
499 }
500
501 /**
502 * @brief Construct string initialized by a character %array.
503 * @param __s Source character %array.
504 * @param __n Number of characters to copy.
505 * @param __a Allocator to use (default is default allocator).
506 *
507 * NB: @a __s must have at least @a __n characters, &apos;\\0&apos;
508 * has no special meaning.
509 */
510 basic_string(const _CharT* __s, size_type __n,
511 const _Alloc& __a = _Alloc())
512 : _M_dataplus(_M_local_data(), __a)
513 { _M_construct(__s, __s + __n); }
514
515 /**
516 * @brief Construct string as copy of a C string.
517 * @param __s Source C string.
518 * @param __a Allocator to use (default is default allocator).
519 */
520#if __cpp_deduction_guides && ! defined _GLIBCXX_DEFINING_STRING_INSTANTIATIONS
521 // _GLIBCXX_RESOLVE_LIB_DEFECTS
522 // 3076. basic_string CTAD ambiguity
523 template<typename = _RequireAllocator<_Alloc>>
524#endif
525 basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
526 : _M_dataplus(_M_local_data(), __a)
527 { _M_construct(__s, __s ? __s + traits_type::length(__s) : __s+npos); }
528
529 /**
530 * @brief Construct string as multiple characters.
531 * @param __n Number of characters.
532 * @param __c Character to use.
533 * @param __a Allocator to use (default is default allocator).
534 */
535#if __cpp_deduction_guides && ! defined _GLIBCXX_DEFINING_STRING_INSTANTIATIONS
536 // _GLIBCXX_RESOLVE_LIB_DEFECTS
537 // 3076. basic_string CTAD ambiguity
538 template<typename = _RequireAllocator<_Alloc>>
539#endif
540 basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc())
541 : _M_dataplus(_M_local_data(), __a)
542 { _M_construct(__n, __c); }
543
544#if __cplusplus201402L >= 201103L
545 /**
546 * @brief Move construct string.
547 * @param __str Source string.
548 *
549 * The newly-created string contains the exact contents of @a __str.
550 * @a __str is a valid, but unspecified string.
551 **/
552 basic_string(basic_string&& __str) noexcept
553 : _M_dataplus(_M_local_data(), std::move(__str._M_get_allocator()))
554 {
555 if (__str._M_is_local())
556 {
557 traits_type::copy(_M_local_buf, __str._M_local_buf,
558 _S_local_capacity + 1);
559 }
560 else
561 {
562 _M_data(__str._M_data());
563 _M_capacity(__str._M_allocated_capacity);
564 }
565
566 // Must use _M_length() here not _M_set_length() because
567 // basic_stringbuf relies on writing into unallocated capacity so
568 // we mess up the contents if we put a '\0' in the string.
569 _M_length(__str.length());
570 __str._M_data(__str._M_local_data());
571 __str._M_set_length(0);
572 }
573
574 /**
575 * @brief Construct string from an initializer %list.
576 * @param __l std::initializer_list of characters.
577 * @param __a Allocator to use (default is default allocator).
578 */
579 basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc())
580 : _M_dataplus(_M_local_data(), __a)
581 { _M_construct(__l.begin(), __l.end()); }
582
583 basic_string(const basic_string& __str, const _Alloc& __a)
584 : _M_dataplus(_M_local_data(), __a)
585 { _M_construct(__str.begin(), __str.end()); }
586
587 basic_string(basic_string&& __str, const _Alloc& __a)
588 noexcept(_Alloc_traits::_S_always_equal())
589 : _M_dataplus(_M_local_data(), __a)
590 {
591 if (__str._M_is_local())
592 {
593 traits_type::copy(_M_local_buf, __str._M_local_buf,
594 _S_local_capacity + 1);
595 _M_length(__str.length());
596 __str._M_set_length(0);
597 }
598 else if (_Alloc_traits::_S_always_equal()
599 || __str.get_allocator() == __a)
600 {
601 _M_data(__str._M_data());
602 _M_length(__str.length());
603 _M_capacity(__str._M_allocated_capacity);
604 __str._M_data(__str._M_local_buf);
605 __str._M_set_length(0);
606 }
607 else
608 _M_construct(__str.begin(), __str.end());
609 }
610
611#endif // C++11
612
613 /**
614 * @brief Construct string as copy of a range.
615 * @param __beg Start of range.
616 * @param __end End of range.
617 * @param __a Allocator to use (default is default allocator).
618 */
619#if __cplusplus201402L >= 201103L
620 template<typename _InputIterator,
621 typename = std::_RequireInputIter<_InputIterator>>
622#else
623 template<typename _InputIterator>
624#endif
625 basic_string(_InputIterator __beg, _InputIterator __end,
626 const _Alloc& __a = _Alloc())
627 : _M_dataplus(_M_local_data(), __a)
628 { _M_construct(__beg, __end); }
629
630#if __cplusplus201402L >= 201703L
631 /**
632 * @brief Construct string from a substring of a string_view.
633 * @param __t Source object convertible to string view.
634 * @param __pos The index of the first character to copy from __t.
635 * @param __n The number of characters to copy from __t.
636 * @param __a Allocator to use.
637 */
638 template<typename _Tp, typename = _If_sv<_Tp, void>>
639 basic_string(const _Tp& __t, size_type __pos, size_type __n,
640 const _Alloc& __a = _Alloc())
641 : basic_string(_S_to_string_view(__t).substr(__pos, __n), __a) { }
642
643 /**
644 * @brief Construct string from a string_view.
645 * @param __t Source object convertible to string view.
646 * @param __a Allocator to use (default is default allocator).
647 */
648 template<typename _Tp, typename = _If_sv<_Tp, void>>
649 explicit
650 basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
651 : basic_string(__sv_wrapper(_S_to_string_view(__t)), __a) { }
652#endif // C++17
653
654 /**
655 * @brief Destroy the string instance.
656 */
657 ~basic_string()
658 { _M_dispose(); }
659
660 /**
661 * @brief Assign the value of @a str to this string.
662 * @param __str Source string.
663 */
664 basic_string&
665 operator=(const basic_string& __str)
666 {
667 return this->assign(__str);
668 }
669
670 /**
671 * @brief Copy contents of @a s into this string.
672 * @param __s Source null-terminated string.
673 */
674 basic_string&
675 operator=(const _CharT* __s)
676 { return this->assign(__s); }
677
678 /**
679 * @brief Set value to string of length 1.
680 * @param __c Source character.
681 *
682 * Assigning to a character makes this string length 1 and
683 * (*this)[0] == @a c.
684 */
685 basic_string&
686 operator=(_CharT __c)
687 {
688 this->assign(1, __c);
689 return *this;
690 }
691
692#if __cplusplus201402L >= 201103L
693 /**
694 * @brief Move assign the value of @a str to this string.
695 * @param __str Source string.
696 *
697 * The contents of @a str are moved into this string (without copying).
698 * @a str is a valid, but unspecified string.
699 **/
700 // _GLIBCXX_RESOLVE_LIB_DEFECTS
701 // 2063. Contradictory requirements for string move assignment
702 basic_string&
703 operator=(basic_string&& __str)
704 noexcept(_Alloc_traits::_S_nothrow_move())
705 {
706 if (!_M_is_local() && _Alloc_traits::_S_propagate_on_move_assign()
707 && !_Alloc_traits::_S_always_equal()
708 && _M_get_allocator() != __str._M_get_allocator())
709 {
710 // Destroy existing storage before replacing allocator.
711 _M_destroy(_M_allocated_capacity);
712 _M_data(_M_local_data());
713 _M_set_length(0);
714 }
715 // Replace allocator if POCMA is true.
716 std::__alloc_on_move(_M_get_allocator(), __str._M_get_allocator());
717
718 if (__str._M_is_local())
719 {
720 // We've always got room for a short string, just copy it.
721 if (__str.size())
722 this->_S_copy(_M_data(), __str._M_data(), __str.size());
723 _M_set_length(__str.size());
724 }
725 else if (_Alloc_traits::_S_propagate_on_move_assign()
726 || _Alloc_traits::_S_always_equal()
727 || _M_get_allocator() == __str._M_get_allocator())
728 {
729 // Just move the allocated pointer, our allocator can free it.
730 pointer __data = nullptr;
731 size_type __capacity;
732 if (!_M_is_local())
733 {
734 if (_Alloc_traits::_S_always_equal())
735 {
736 // __str can reuse our existing storage.
737 __data = _M_data();
738 __capacity = _M_allocated_capacity;
739 }
740 else // __str can't use it, so free it.
741 _M_destroy(_M_allocated_capacity);
742 }
743
744 _M_data(__str._M_data());
745 _M_length(__str.length());
746 _M_capacity(__str._M_allocated_capacity);
747 if (__data)
748 {
749 __str._M_data(__data);
750 __str._M_capacity(__capacity);
751 }
752 else
753 __str._M_data(__str._M_local_buf);
754 }
755 else // Need to do a deep copy
756 assign(__str);
757 __str.clear();
758 return *this;
759 }
760
761 /**
762 * @brief Set value to string constructed from initializer %list.
763 * @param __l std::initializer_list.
764 */
765 basic_string&
766 operator=(initializer_list<_CharT> __l)
767 {
768 this->assign(__l.begin(), __l.size());
769 return *this;
770 }
771#endif // C++11
772
773#if __cplusplus201402L >= 201703L
774 /**
775 * @brief Set value to string constructed from a string_view.
776 * @param __svt An object convertible to string_view.
777 */
778 template<typename _Tp>
779 _If_sv<_Tp, basic_string&>
780 operator=(const _Tp& __svt)
781 { return this->assign(__svt); }
782
783 /**
784 * @brief Convert to a string_view.
785 * @return A string_view.
786 */
787 operator __sv_type() const noexcept
788 { return __sv_type(data(), size()); }
789#endif // C++17
790
791 // Iterators:
792 /**
793 * Returns a read/write iterator that points to the first character in
794 * the %string.
795 */
796 iterator
797 begin() _GLIBCXX_NOEXCEPTnoexcept
798 { return iterator(_M_data()); }
799
800 /**
801 * Returns a read-only (constant) iterator that points to the first
802 * character in the %string.
803 */
804 const_iterator
805 begin() const _GLIBCXX_NOEXCEPTnoexcept
806 { return const_iterator(_M_data()); }
807
808 /**
809 * Returns a read/write iterator that points one past the last
810 * character in the %string.
811 */
812 iterator
813 end() _GLIBCXX_NOEXCEPTnoexcept
814 { return iterator(_M_data() + this->size()); }
815
816 /**
817 * Returns a read-only (constant) iterator that points one past the
818 * last character in the %string.
819 */
820 const_iterator
821 end() const _GLIBCXX_NOEXCEPTnoexcept
822 { return const_iterator(_M_data() + this->size()); }
823
824 /**
825 * Returns a read/write reverse iterator that points to the last
826 * character in the %string. Iteration is done in reverse element
827 * order.
828 */
829 reverse_iterator
830 rbegin() _GLIBCXX_NOEXCEPTnoexcept
831 { return reverse_iterator(this->end()); }
832
833 /**
834 * Returns a read-only (constant) reverse iterator that points
835 * to the last character in the %string. Iteration is done in
836 * reverse element order.
837 */
838 const_reverse_iterator
839 rbegin() const _GLIBCXX_NOEXCEPTnoexcept
840 { return const_reverse_iterator(this->end()); }
841
842 /**
843 * Returns a read/write reverse iterator that points to one before the
844 * first character in the %string. Iteration is done in reverse
845 * element order.
846 */
847 reverse_iterator
848 rend() _GLIBCXX_NOEXCEPTnoexcept
849 { return reverse_iterator(this->begin()); }
850
851 /**
852 * Returns a read-only (constant) reverse iterator that points
853 * to one before the first character in the %string. Iteration
854 * is done in reverse element order.
855 */
856 const_reverse_iterator
857 rend() const _GLIBCXX_NOEXCEPTnoexcept
858 { return const_reverse_iterator(this->begin()); }
859
860#if __cplusplus201402L >= 201103L
861 /**
862 * Returns a read-only (constant) iterator that points to the first
863 * character in the %string.
864 */
865 const_iterator
866 cbegin() const noexcept
867 { return const_iterator(this->_M_data()); }
868
869 /**
870 * Returns a read-only (constant) iterator that points one past the
871 * last character in the %string.
872 */
873 const_iterator
874 cend() const noexcept
875 { return const_iterator(this->_M_data() + this->size()); }
876
877 /**
878 * Returns a read-only (constant) reverse iterator that points
879 * to the last character in the %string. Iteration is done in
880 * reverse element order.
881 */
882 const_reverse_iterator
883 crbegin() const noexcept
884 { return const_reverse_iterator(this->end()); }
885
886 /**
887 * Returns a read-only (constant) reverse iterator that points
888 * to one before the first character in the %string. Iteration
889 * is done in reverse element order.
890 */
891 const_reverse_iterator
892 crend() const noexcept
893 { return const_reverse_iterator(this->begin()); }
894#endif
895
896 public:
897 // Capacity:
898 /// Returns the number of characters in the string, not including any
899 /// null-termination.
900 size_type
901 size() const _GLIBCXX_NOEXCEPTnoexcept
902 { return _M_string_length; }
903
904 /// Returns the number of characters in the string, not including any
905 /// null-termination.
906 size_type
907 length() const _GLIBCXX_NOEXCEPTnoexcept
908 { return _M_string_length; }
909
910 /// Returns the size() of the largest possible %string.
911 size_type
912 max_size() const _GLIBCXX_NOEXCEPTnoexcept
913 { return (_Alloc_traits::max_size(_M_get_allocator()) - 1) / 2; }
914
915 /**
916 * @brief Resizes the %string to the specified number of characters.
917 * @param __n Number of characters the %string should contain.
918 * @param __c Character to fill any new elements.
919 *
920 * This function will %resize the %string to the specified
921 * number of characters. If the number is smaller than the
922 * %string's current size the %string is truncated, otherwise
923 * the %string is extended and new elements are %set to @a __c.
924 */
925 void
926 resize(size_type __n, _CharT __c);
927
928 /**
929 * @brief Resizes the %string to the specified number of characters.
930 * @param __n Number of characters the %string should contain.
931 *
932 * This function will resize the %string to the specified length. If
933 * the new size is smaller than the %string's current size the %string
934 * is truncated, otherwise the %string is extended and new characters
935 * are default-constructed. For basic types such as char, this means
936 * setting them to 0.
937 */
938 void
939 resize(size_type __n)
940 { this->resize(__n, _CharT()); }
941
942#if __cplusplus201402L >= 201103L
943 /// A non-binding request to reduce capacity() to size().
944 void
945 shrink_to_fit() noexcept
946 {
947#if __cpp_exceptions
948 if (capacity() > size())
949 {
950 try
951 { reserve(0); }
952 catch(...)
953 { }
954 }
955#endif
956 }
957#endif
958
959 /**
960 * Returns the total number of characters that the %string can hold
961 * before needing to allocate more memory.
962 */
963 size_type
964 capacity() const _GLIBCXX_NOEXCEPTnoexcept
965 {
966 return _M_is_local() ? size_type(_S_local_capacity)
967 : _M_allocated_capacity;
968 }
969
970 /**
971 * @brief Attempt to preallocate enough memory for specified number of
972 * characters.
973 * @param __res_arg Number of characters required.
974 * @throw std::length_error If @a __res_arg exceeds @c max_size().
975 *
976 * This function attempts to reserve enough memory for the
977 * %string to hold the specified number of characters. If the
978 * number requested is more than max_size(), length_error is
979 * thrown.
980 *
981 * The advantage of this function is that if optimal code is a
982 * necessity and the user can determine the string length that will be
983 * required, the user can reserve the memory in %advance, and thus
984 * prevent a possible reallocation of memory and copying of %string
985 * data.
986 */
987 void
988 reserve(size_type __res_arg = 0);
989
990 /**
991 * Erases the string, making it empty.
992 */
993 void
994 clear() _GLIBCXX_NOEXCEPTnoexcept
995 { _M_set_length(0); }
996
997 /**
998 * Returns true if the %string is empty. Equivalent to
999 * <code>*this == ""</code>.
1000 */
1001 _GLIBCXX_NODISCARD bool
1002 empty() const _GLIBCXX_NOEXCEPTnoexcept
1003 { return this->size() == 0; }
1004
1005 // Element access:
1006 /**
1007 * @brief Subscript access to the data contained in the %string.
1008 * @param __pos The index of the character to access.
1009 * @return Read-only (constant) reference to the character.
1010 *
1011 * This operator allows for easy, array-style, data access.
1012 * Note that data access with this operator is unchecked and
1013 * out_of_range lookups are not defined. (For checked lookups
1014 * see at().)
1015 */
1016 const_reference
1017 operator[] (size_type __pos) const _GLIBCXX_NOEXCEPTnoexcept
1018 {
1019 __glibcxx_assert(__pos <= size());
1020 return _M_data()[__pos];
1021 }
1022
1023 /**
1024 * @brief Subscript access to the data contained in the %string.
1025 * @param __pos The index of the character to access.
1026 * @return Read/write reference to the character.
1027 *
1028 * This operator allows for easy, array-style, data access.
1029 * Note that data access with this operator is unchecked and
1030 * out_of_range lookups are not defined. (For checked lookups
1031 * see at().)
1032 */
1033 reference
1034 operator[](size_type __pos)
1035 {
1036 // Allow pos == size() both in C++98 mode, as v3 extension,
1037 // and in C++11 mode.
1038 __glibcxx_assert(__pos <= size());
1039 // In pedantic mode be strict in C++98 mode.
1040 _GLIBCXX_DEBUG_PEDASSERT(__cplusplus >= 201103L || __pos < size());
1041 return _M_data()[__pos];
1042 }
1043
1044 /**
1045 * @brief Provides access to the data contained in the %string.
1046 * @param __n The index of the character to access.
1047 * @return Read-only (const) reference to the character.
1048 * @throw std::out_of_range If @a n is an invalid index.
1049 *
1050 * This function provides for safer data access. The parameter is
1051 * first checked that it is in the range of the string. The function
1052 * throws out_of_range if the check fails.
1053 */
1054 const_reference
1055 at(size_type __n) const
1056 {
1057 if (__n >= this->size())
1058 __throw_out_of_range_fmt(__N("basic_string::at: __n "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
1059 "(which is %zu) >= this->size() "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
1060 "(which is %zu)")("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)"),
1061 __n, this->size());
1062 return _M_data()[__n];
1063 }
1064
1065 /**
1066 * @brief Provides access to the data contained in the %string.
1067 * @param __n The index of the character to access.
1068 * @return Read/write reference to the character.
1069 * @throw std::out_of_range If @a n is an invalid index.
1070 *
1071 * This function provides for safer data access. The parameter is
1072 * first checked that it is in the range of the string. The function
1073 * throws out_of_range if the check fails.
1074 */
1075 reference
1076 at(size_type __n)
1077 {
1078 if (__n >= size())
1079 __throw_out_of_range_fmt(__N("basic_string::at: __n "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
1080 "(which is %zu) >= this->size() "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
1081 "(which is %zu)")("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)"),
1082 __n, this->size());
1083 return _M_data()[__n];
1084 }
1085
1086#if __cplusplus201402L >= 201103L
1087 /**
1088 * Returns a read/write reference to the data at the first
1089 * element of the %string.
1090 */
1091 reference
1092 front() noexcept
1093 {
1094 __glibcxx_assert(!empty());
1095 return operator[](0);
1096 }
1097
1098 /**
1099 * Returns a read-only (constant) reference to the data at the first
1100 * element of the %string.
1101 */
1102 const_reference
1103 front() const noexcept
1104 {
1105 __glibcxx_assert(!empty());
1106 return operator[](0);
1107 }
1108
1109 /**
1110 * Returns a read/write reference to the data at the last
1111 * element of the %string.
1112 */
1113 reference
1114 back() noexcept
1115 {
1116 __glibcxx_assert(!empty());
1117 return operator[](this->size() - 1);
1118 }
1119
1120 /**
1121 * Returns a read-only (constant) reference to the data at the
1122 * last element of the %string.
1123 */
1124 const_reference
1125 back() const noexcept
1126 {
1127 __glibcxx_assert(!empty());
1128 return operator[](this->size() - 1);
1129 }
1130#endif
1131
1132 // Modifiers:
1133 /**
1134 * @brief Append a string to this string.
1135 * @param __str The string to append.
1136 * @return Reference to this string.
1137 */
1138 basic_string&
1139 operator+=(const basic_string& __str)
1140 { return this->append(__str); }
1141
1142 /**
1143 * @brief Append a C string.
1144 * @param __s The C string to append.
1145 * @return Reference to this string.
1146 */
1147 basic_string&
1148 operator+=(const _CharT* __s)
1149 { return this->append(__s); }
1150
1151 /**
1152 * @brief Append a character.
1153 * @param __c The character to append.
1154 * @return Reference to this string.
1155 */
1156 basic_string&
1157 operator+=(_CharT __c)
1158 {
1159 this->push_back(__c);
1160 return *this;
1161 }
1162
1163#if __cplusplus201402L >= 201103L
1164 /**
1165 * @brief Append an initializer_list of characters.
1166 * @param __l The initializer_list of characters to be appended.
1167 * @return Reference to this string.
1168 */
1169 basic_string&
1170 operator+=(initializer_list<_CharT> __l)
1171 { return this->append(__l.begin(), __l.size()); }
1172#endif // C++11
1173
1174#if __cplusplus201402L >= 201703L
1175 /**
1176 * @brief Append a string_view.
1177 * @param __svt An object convertible to string_view to be appended.
1178 * @return Reference to this string.
1179 */
1180 template<typename _Tp>
1181 _If_sv<_Tp, basic_string&>
1182 operator+=(const _Tp& __svt)
1183 { return this->append(__svt); }
1184#endif // C++17
1185
1186 /**
1187 * @brief Append a string to this string.
1188 * @param __str The string to append.
1189 * @return Reference to this string.
1190 */
1191 basic_string&
1192 append(const basic_string& __str)
1193 { return _M_append(__str._M_data(), __str.size()); }
1194
1195 /**
1196 * @brief Append a substring.
1197 * @param __str The string to append.
1198 * @param __pos Index of the first character of str to append.
1199 * @param __n The number of characters to append.
1200 * @return Reference to this string.
1201 * @throw std::out_of_range if @a __pos is not a valid index.
1202 *
1203 * This function appends @a __n characters from @a __str
1204 * starting at @a __pos to this string. If @a __n is is larger
1205 * than the number of available characters in @a __str, the
1206 * remainder of @a __str is appended.
1207 */
1208 basic_string&
1209 append(const basic_string& __str, size_type __pos, size_type __n = npos)
1210 { return _M_append(__str._M_data()
1211 + __str._M_check(__pos, "basic_string::append"),
1212 __str._M_limit(__pos, __n)); }
1213
1214 /**
1215 * @brief Append a C substring.
1216 * @param __s The C string to append.
1217 * @param __n The number of characters to append.
1218 * @return Reference to this string.
1219 */
1220 basic_string&
1221 append(const _CharT* __s, size_type __n)
1222 {
1223 __glibcxx_requires_string_len(__s, __n);
1224 _M_check_length(size_type(0), __n, "basic_string::append");
1225 return _M_append(__s, __n);
1226 }
1227
1228 /**
1229 * @brief Append a C string.
1230 * @param __s The C string to append.
1231 * @return Reference to this string.
1232 */
1233 basic_string&
1234 append(const _CharT* __s)
1235 {
1236 __glibcxx_requires_string(__s);
1237 const size_type __n = traits_type::length(__s);
1238 _M_check_length(size_type(0), __n, "basic_string::append");
1239 return _M_append(__s, __n);
1240 }
1241
1242 /**
1243 * @brief Append multiple characters.
1244 * @param __n The number of characters to append.
1245 * @param __c The character to use.
1246 * @return Reference to this string.
1247 *
1248 * Appends __n copies of __c to this string.
1249 */
1250 basic_string&
1251 append(size_type __n, _CharT __c)
1252 { return _M_replace_aux(this->size(), size_type(0), __n, __c); }
1253
1254#if __cplusplus201402L >= 201103L
1255 /**
1256 * @brief Append an initializer_list of characters.
1257 * @param __l The initializer_list of characters to append.
1258 * @return Reference to this string.
1259 */
1260 basic_string&
1261 append(initializer_list<_CharT> __l)
1262 { return this->append(__l.begin(), __l.size()); }
1263#endif // C++11
1264
1265 /**
1266 * @brief Append a range of characters.
1267 * @param __first Iterator referencing the first character to append.
1268 * @param __last Iterator marking the end of the range.
1269 * @return Reference to this string.
1270 *
1271 * Appends characters in the range [__first,__last) to this string.
1272 */
1273#if __cplusplus201402L >= 201103L
1274 template<class _InputIterator,
1275 typename = std::_RequireInputIter<_InputIterator>>
1276#else
1277 template<class _InputIterator>
1278#endif
1279 basic_string&
1280 append(_InputIterator __first, _InputIterator __last)
1281 { return this->replace(end(), end(), __first, __last); }
1282
1283#if __cplusplus201402L >= 201703L
1284 /**
1285 * @brief Append a string_view.
1286 * @param __svt An object convertible to string_view to be appended.
1287 * @return Reference to this string.
1288 */
1289 template<typename _Tp>
1290 _If_sv<_Tp, basic_string&>
1291 append(const _Tp& __svt)
1292 {
1293 __sv_type __sv = __svt;
1294 return this->append(__sv.data(), __sv.size());
1295 }
1296
1297 /**
1298 * @brief Append a range of characters from a string_view.
1299 * @param __svt An object convertible to string_view to be appended from.
1300 * @param __pos The position in the string_view to append from.
1301 * @param __n The number of characters to append from the string_view.
1302 * @return Reference to this string.
1303 */
1304 template<typename _Tp>
1305 _If_sv<_Tp, basic_string&>
1306 append(const _Tp& __svt, size_type __pos, size_type __n = npos)
1307 {
1308 __sv_type __sv = __svt;
1309 return _M_append(__sv.data()
1310 + std::__sv_check(__sv.size(), __pos, "basic_string::append"),
1311 std::__sv_limit(__sv.size(), __pos, __n));
1312 }
1313#endif // C++17
1314
1315 /**
1316 * @brief Append a single character.
1317 * @param __c Character to append.
1318 */
1319 void
1320 push_back(_CharT __c)
1321 {
1322 const size_type __size = this->size();
1323 if (__size + 1 > this->capacity())
1324 this->_M_mutate(__size, size_type(0), 0, size_type(1));
1325 traits_type::assign(this->_M_data()[__size], __c);
1326 this->_M_set_length(__size + 1);
1327 }
1328
1329 /**
1330 * @brief Set value to contents of another string.
1331 * @param __str Source string to use.
1332 * @return Reference to this string.
1333 */
1334 basic_string&
1335 assign(const basic_string& __str)
1336 {
1337#if __cplusplus201402L >= 201103L
1338 if (_Alloc_traits::_S_propagate_on_copy_assign())
1339 {
1340 if (!_Alloc_traits::_S_always_equal() && !_M_is_local()
1341 && _M_get_allocator() != __str._M_get_allocator())
1342 {
1343 // Propagating allocator cannot free existing storage so must
1344 // deallocate it before replacing current allocator.
1345 if (__str.size() <= _S_local_capacity)
1346 {
1347 _M_destroy(_M_allocated_capacity);
1348 _M_data(_M_local_data());
1349 _M_set_length(0);
1350 }
1351 else
1352 {
1353 const auto __len = __str.size();
1354 auto __alloc = __str._M_get_allocator();
1355 // If this allocation throws there are no effects:
1356 auto __ptr = _Alloc_traits::allocate(__alloc, __len + 1);
1357 _M_destroy(_M_allocated_capacity);
1358 _M_data(__ptr);
1359 _M_capacity(__len);
1360 _M_set_length(__len);
1361 }
1362 }
1363 std::__alloc_on_copy(_M_get_allocator(), __str._M_get_allocator());
1364 }
1365#endif
1366 this->_M_assign(__str);
1367 return *this;
1368 }
1369
1370#if __cplusplus201402L >= 201103L
1371 /**
1372 * @brief Set value to contents of another string.
1373 * @param __str Source string to use.
1374 * @return Reference to this string.
1375 *
1376 * This function sets this string to the exact contents of @a __str.
1377 * @a __str is a valid, but unspecified string.
1378 */
1379 basic_string&
1380 assign(basic_string&& __str)
1381 noexcept(_Alloc_traits::_S_nothrow_move())
1382 {
1383 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1384 // 2063. Contradictory requirements for string move assignment
1385 return *this = std::move(__str);
1386 }
1387#endif // C++11
1388
1389 /**
1390 * @brief Set value to a substring of a string.
1391 * @param __str The string to use.
1392 * @param __pos Index of the first character of str.
1393 * @param __n Number of characters to use.
1394 * @return Reference to this string.
1395 * @throw std::out_of_range if @a pos is not a valid index.
1396 *
1397 * This function sets this string to the substring of @a __str
1398 * consisting of @a __n characters at @a __pos. If @a __n is
1399 * is larger than the number of available characters in @a
1400 * __str, the remainder of @a __str is used.
1401 */
1402 basic_string&
1403 assign(const basic_string& __str, size_type __pos, size_type __n = npos)
1404 { return _M_replace(size_type(0), this->size(), __str._M_data()
1405 + __str._M_check(__pos, "basic_string::assign"),
1406 __str._M_limit(__pos, __n)); }
1407
1408 /**
1409 * @brief Set value to a C substring.
1410 * @param __s The C string to use.
1411 * @param __n Number of characters to use.
1412 * @return Reference to this string.
1413 *
1414 * This function sets the value of this string to the first @a __n
1415 * characters of @a __s. If @a __n is is larger than the number of
1416 * available characters in @a __s, the remainder of @a __s is used.
1417 */
1418 basic_string&
1419 assign(const _CharT* __s, size_type __n)
1420 {
1421 __glibcxx_requires_string_len(__s, __n);
1422 return _M_replace(size_type(0), this->size(), __s, __n);
1423 }
1424
1425 /**
1426 * @brief Set value to contents of a C string.
1427 * @param __s The C string to use.
1428 * @return Reference to this string.
1429 *
1430 * This function sets the value of this string to the value of @a __s.
1431 * The data is copied, so there is no dependence on @a __s once the
1432 * function returns.
1433 */
1434 basic_string&
1435 assign(const _CharT* __s)
1436 {
1437 __glibcxx_requires_string(__s);
1438 return _M_replace(size_type(0), this->size(), __s,
1439 traits_type::length(__s));
1440 }
1441
1442 /**
1443 * @brief Set value to multiple characters.
1444 * @param __n Length of the resulting string.
1445 * @param __c The character to use.
1446 * @return Reference to this string.
1447 *
1448 * This function sets the value of this string to @a __n copies of
1449 * character @a __c.
1450 */
1451 basic_string&
1452 assign(size_type __n, _CharT __c)
1453 { return _M_replace_aux(size_type(0), this->size(), __n, __c); }
1454
1455 /**
1456 * @brief Set value to a range of characters.
1457 * @param __first Iterator referencing the first character to append.
1458 * @param __last Iterator marking the end of the range.
1459 * @return Reference to this string.
1460 *
1461 * Sets value of string to characters in the range [__first,__last).
1462 */
1463#if __cplusplus201402L >= 201103L
1464 template<class _InputIterator,
1465 typename = std::_RequireInputIter<_InputIterator>>
1466#else
1467 template<class _InputIterator>
1468#endif
1469 basic_string&
1470 assign(_InputIterator __first, _InputIterator __last)
1471 { return this->replace(begin(), end(), __first, __last); }
1472
1473#if __cplusplus201402L >= 201103L
1474 /**
1475 * @brief Set value to an initializer_list of characters.
1476 * @param __l The initializer_list of characters to assign.
1477 * @return Reference to this string.
1478 */
1479 basic_string&
1480 assign(initializer_list<_CharT> __l)
1481 { return this->assign(__l.begin(), __l.size()); }
1482#endif // C++11
1483
1484#if __cplusplus201402L >= 201703L
1485 /**
1486 * @brief Set value from a string_view.
1487 * @param __svt The source object convertible to string_view.
1488 * @return Reference to this string.
1489 */
1490 template<typename _Tp>
1491 _If_sv<_Tp, basic_string&>
1492 assign(const _Tp& __svt)
1493 {
1494 __sv_type __sv = __svt;
1495 return this->assign(__sv.data(), __sv.size());
1496 }
1497
1498 /**
1499 * @brief Set value from a range of characters in a string_view.
1500 * @param __svt The source object convertible to string_view.
1501 * @param __pos The position in the string_view to assign from.
1502 * @param __n The number of characters to assign.
1503 * @return Reference to this string.
1504 */
1505 template<typename _Tp>
1506 _If_sv<_Tp, basic_string&>
1507 assign(const _Tp& __svt, size_type __pos, size_type __n = npos)
1508 {
1509 __sv_type __sv = __svt;
1510 return _M_replace(size_type(0), this->size(),
1511 __sv.data()
1512 + std::__sv_check(__sv.size(), __pos, "basic_string::assign"),
1513 std::__sv_limit(__sv.size(), __pos, __n));
1514 }
1515#endif // C++17
1516
1517#if __cplusplus201402L >= 201103L
1518 /**
1519 * @brief Insert multiple characters.
1520 * @param __p Const_iterator referencing location in string to
1521 * insert at.
1522 * @param __n Number of characters to insert
1523 * @param __c The character to insert.
1524 * @return Iterator referencing the first inserted char.
1525 * @throw std::length_error If new length exceeds @c max_size().
1526 *
1527 * Inserts @a __n copies of character @a __c starting at the
1528 * position referenced by iterator @a __p. If adding
1529 * characters causes the length to exceed max_size(),
1530 * length_error is thrown. The value of the string doesn't
1531 * change if an error is thrown.
1532 */
1533 iterator
1534 insert(const_iterator __p, size_type __n, _CharT __c)
1535 {
1536 _GLIBCXX_DEBUG_PEDASSERT(__p >= begin() && __p <= end());
1537 const size_type __pos = __p - begin();
1538 this->replace(__p, __p, __n, __c);
1539 return iterator(this->_M_data() + __pos);
1540 }
1541#else
1542 /**
1543 * @brief Insert multiple characters.
1544 * @param __p Iterator referencing location in string to insert at.
1545 * @param __n Number of characters to insert
1546 * @param __c The character to insert.
1547 * @throw std::length_error If new length exceeds @c max_size().
1548 *
1549 * Inserts @a __n copies of character @a __c starting at the
1550 * position referenced by iterator @a __p. If adding
1551 * characters causes the length to exceed max_size(),
1552 * length_error is thrown. The value of the string doesn't
1553 * change if an error is thrown.
1554 */
1555 void
1556 insert(iterator __p, size_type __n, _CharT __c)
1557 { this->replace(__p, __p, __n, __c); }
1558#endif
1559
1560#if __cplusplus201402L >= 201103L
1561 /**
1562 * @brief Insert a range of characters.
1563 * @param __p Const_iterator referencing location in string to
1564 * insert at.
1565 * @param __beg Start of range.
1566 * @param __end End of range.
1567 * @return Iterator referencing the first inserted char.
1568 * @throw std::length_error If new length exceeds @c max_size().
1569 *
1570 * Inserts characters in range [beg,end). If adding characters
1571 * causes the length to exceed max_size(), length_error is
1572 * thrown. The value of the string doesn't change if an error
1573 * is thrown.
1574 */
1575 template<class _InputIterator,
1576 typename = std::_RequireInputIter<_InputIterator>>
1577 iterator
1578 insert(const_iterator __p, _InputIterator __beg, _InputIterator __end)
1579 {
1580 _GLIBCXX_DEBUG_PEDASSERT(__p >= begin() && __p <= end());
1581 const size_type __pos = __p - begin();
1582 this->replace(__p, __p, __beg, __end);
1583 return iterator(this->_M_data() + __pos);
1584 }
1585#else
1586 /**
1587 * @brief Insert a range of characters.
1588 * @param __p Iterator referencing location in string to insert at.
1589 * @param __beg Start of range.
1590 * @param __end End of range.
1591 * @throw std::length_error If new length exceeds @c max_size().
1592 *
1593 * Inserts characters in range [__beg,__end). If adding
1594 * characters causes the length to exceed max_size(),
1595 * length_error is thrown. The value of the string doesn't
1596 * change if an error is thrown.
1597 */
1598 template<class _InputIterator>
1599 void
1600 insert(iterator __p, _InputIterator __beg, _InputIterator __end)
1601 { this->replace(__p, __p, __beg, __end); }
1602#endif
1603
1604#if __cplusplus201402L >= 201103L
1605 /**
1606 * @brief Insert an initializer_list of characters.
1607 * @param __p Iterator referencing location in string to insert at.
1608 * @param __l The initializer_list of characters to insert.
1609 * @throw std::length_error If new length exceeds @c max_size().
1610 */
1611 iterator
1612 insert(const_iterator __p, initializer_list<_CharT> __l)
1613 { return this->insert(__p, __l.begin(), __l.end()); }
1614
1615#ifdef _GLIBCXX_DEFINING_STRING_INSTANTIATIONS
1616 // See PR libstdc++/83328
1617 void
1618 insert(iterator __p, initializer_list<_CharT> __l)
1619 {
1620 _GLIBCXX_DEBUG_PEDASSERT(__p >= begin() && __p <= end());
1621 this->insert(__p - begin(), __l.begin(), __l.size());
1622 }
1623#endif
1624#endif // C++11
1625
1626 /**
1627 * @brief Insert value of a string.
1628 * @param __pos1 Position in string to insert at.
1629 * @param __str The string to insert.
1630 * @return Reference to this string.
1631 * @throw std::length_error If new length exceeds @c max_size().
1632 *
1633 * Inserts value of @a __str starting at @a __pos1. If adding
1634 * characters causes the length to exceed max_size(),
1635 * length_error is thrown. The value of the string doesn't
1636 * change if an error is thrown.
1637 */
1638 basic_string&
1639 insert(size_type __pos1, const basic_string& __str)
1640 { return this->replace(__pos1, size_type(0),
1641 __str._M_data(), __str.size()); }
1642
1643 /**
1644 * @brief Insert a substring.
1645 * @param __pos1 Position in string to insert at.
1646 * @param __str The string to insert.
1647 * @param __pos2 Start of characters in str to insert.
1648 * @param __n Number of characters to insert.
1649 * @return Reference to this string.
1650 * @throw std::length_error If new length exceeds @c max_size().
1651 * @throw std::out_of_range If @a pos1 > size() or
1652 * @a __pos2 > @a str.size().
1653 *
1654 * Starting at @a pos1, insert @a __n character of @a __str
1655 * beginning with @a __pos2. If adding characters causes the
1656 * length to exceed max_size(), length_error is thrown. If @a
1657 * __pos1 is beyond the end of this string or @a __pos2 is
1658 * beyond the end of @a __str, out_of_range is thrown. The
1659 * value of the string doesn't change if an error is thrown.
1660 */
1661 basic_string&
1662 insert(size_type __pos1, const basic_string& __str,
1663 size_type __pos2, size_type __n = npos)
1664 { return this->replace(__pos1, size_type(0), __str._M_data()
1665 + __str._M_check(__pos2, "basic_string::insert"),
1666 __str._M_limit(__pos2, __n)); }
1667
1668 /**
1669 * @brief Insert a C substring.
1670 * @param __pos Position in string to insert at.
1671 * @param __s The C string to insert.
1672 * @param __n The number of characters to insert.
1673 * @return Reference to this string.
1674 * @throw std::length_error If new length exceeds @c max_size().
1675 * @throw std::out_of_range If @a __pos is beyond the end of this
1676 * string.
1677 *
1678 * Inserts the first @a __n characters of @a __s starting at @a
1679 * __pos. If adding characters causes the length to exceed
1680 * max_size(), length_error is thrown. If @a __pos is beyond
1681 * end(), out_of_range is thrown. The value of the string
1682 * doesn't change if an error is thrown.
1683 */
1684 basic_string&
1685 insert(size_type __pos, const _CharT* __s, size_type __n)
1686 { return this->replace(__pos, size_type(0), __s, __n); }
1687
1688 /**
1689 * @brief Insert a C string.
1690 * @param __pos Position in string to insert at.
1691 * @param __s The C string to insert.
1692 * @return Reference to this string.
1693 * @throw std::length_error If new length exceeds @c max_size().
1694 * @throw std::out_of_range If @a pos is beyond the end of this
1695 * string.
1696 *
1697 * Inserts the first @a n characters of @a __s starting at @a __pos. If
1698 * adding characters causes the length to exceed max_size(),
1699 * length_error is thrown. If @a __pos is beyond end(), out_of_range is
1700 * thrown. The value of the string doesn't change if an error is
1701 * thrown.
1702 */
1703 basic_string&
1704 insert(size_type __pos, const _CharT* __s)
1705 {
1706 __glibcxx_requires_string(__s);
1707 return this->replace(__pos, size_type(0), __s,
1708 traits_type::length(__s));
1709 }
1710
1711 /**
1712 * @brief Insert multiple characters.
1713 * @param __pos Index in string to insert at.
1714 * @param __n Number of characters to insert
1715 * @param __c The character to insert.
1716 * @return Reference to this string.
1717 * @throw std::length_error If new length exceeds @c max_size().
1718 * @throw std::out_of_range If @a __pos is beyond the end of this
1719 * string.
1720 *
1721 * Inserts @a __n copies of character @a __c starting at index
1722 * @a __pos. If adding characters causes the length to exceed
1723 * max_size(), length_error is thrown. If @a __pos > length(),
1724 * out_of_range is thrown. The value of the string doesn't
1725 * change if an error is thrown.
1726 */
1727 basic_string&
1728 insert(size_type __pos, size_type __n, _CharT __c)
1729 { return _M_replace_aux(_M_check(__pos, "basic_string::insert"),
1730 size_type(0), __n, __c); }
1731
1732 /**
1733 * @brief Insert one character.
1734 * @param __p Iterator referencing position in string to insert at.
1735 * @param __c The character to insert.
1736 * @return Iterator referencing newly inserted char.
1737 * @throw std::length_error If new length exceeds @c max_size().
1738 *
1739 * Inserts character @a __c at position referenced by @a __p.
1740 * If adding character causes the length to exceed max_size(),
1741 * length_error is thrown. If @a __p is beyond end of string,
1742 * out_of_range is thrown. The value of the string doesn't
1743 * change if an error is thrown.
1744 */
1745 iterator
1746 insert(__const_iterator __p, _CharT __c)
1747 {
1748 _GLIBCXX_DEBUG_PEDASSERT(__p >= begin() && __p <= end());
1749 const size_type __pos = __p - begin();
1750 _M_replace_aux(__pos, size_type(0), size_type(1), __c);
1751 return iterator(_M_data() + __pos);
1752 }
1753
1754#if __cplusplus201402L >= 201703L
1755 /**
1756 * @brief Insert a string_view.
1757 * @param __pos Position in string to insert at.
1758 * @param __svt The object convertible to string_view to insert.
1759 * @return Reference to this string.
1760 */
1761 template<typename _Tp>
1762 _If_sv<_Tp, basic_string&>
1763 insert(size_type __pos, const _Tp& __svt)
1764 {
1765 __sv_type __sv = __svt;
1766 return this->insert(__pos, __sv.data(), __sv.size());
1767 }
1768
1769 /**
1770 * @brief Insert a string_view.
1771 * @param __pos1 Position in string to insert at.
1772 * @param __svt The object convertible to string_view to insert from.
1773 * @param __pos2 Start of characters in str to insert.
1774 * @param __n The number of characters to insert.
1775 * @return Reference to this string.
1776 */
1777 template<typename _Tp>
1778 _If_sv<_Tp, basic_string&>
1779 insert(size_type __pos1, const _Tp& __svt,
1780 size_type __pos2, size_type __n = npos)
1781 {
1782 __sv_type __sv = __svt;
1783 return this->replace(__pos1, size_type(0),
1784 __sv.data()
1785 + std::__sv_check(__sv.size(), __pos2, "basic_string::insert"),
1786 std::__sv_limit(__sv.size(), __pos2, __n));
1787 }
1788#endif // C++17
1789
1790 /**
1791 * @brief Remove characters.
1792 * @param __pos Index of first character to remove (default 0).
1793 * @param __n Number of characters to remove (default remainder).
1794 * @return Reference to this string.
1795 * @throw std::out_of_range If @a pos is beyond the end of this
1796 * string.
1797 *
1798 * Removes @a __n characters from this string starting at @a
1799 * __pos. The length of the string is reduced by @a __n. If
1800 * there are < @a __n characters to remove, the remainder of
1801 * the string is truncated. If @a __p is beyond end of string,
1802 * out_of_range is thrown. The value of the string doesn't
1803 * change if an error is thrown.
1804 */
1805 basic_string&
1806 erase(size_type __pos = 0, size_type __n = npos)
1807 {
1808 _M_check(__pos, "basic_string::erase");
1809 if (__n == npos)
1810 this->_M_set_length(__pos);
1811 else if (__n != 0)
1812 this->_M_erase(__pos, _M_limit(__pos, __n));
1813 return *this;
1814 }
1815
1816 /**
1817 * @brief Remove one character.
1818 * @param __position Iterator referencing the character to remove.
1819 * @return iterator referencing same location after removal.
1820 *
1821 * Removes the character at @a __position from this string. The value
1822 * of the string doesn't change if an error is thrown.
1823 */
1824 iterator
1825 erase(__const_iterator __position)
1826 {
1827 _GLIBCXX_DEBUG_PEDASSERT(__position >= begin()
1828 && __position < end());
1829 const size_type __pos = __position - begin();
1830 this->_M_erase(__pos, size_type(1));
1831 return iterator(_M_data() + __pos);
1832 }
1833
1834 /**
1835 * @brief Remove a range of characters.
1836 * @param __first Iterator referencing the first character to remove.
1837 * @param __last Iterator referencing the end of the range.
1838 * @return Iterator referencing location of first after removal.
1839 *
1840 * Removes the characters in the range [first,last) from this string.
1841 * The value of the string doesn't change if an error is thrown.
1842 */
1843 iterator
1844 erase(__const_iterator __first, __const_iterator __last)
1845 {
1846 _GLIBCXX_DEBUG_PEDASSERT(__first >= begin() && __first <= __last
1847 && __last <= end());
1848 const size_type __pos = __first - begin();
1849 if (__last == end())
1850 this->_M_set_length(__pos);
1851 else
1852 this->_M_erase(__pos, __last - __first);
1853 return iterator(this->_M_data() + __pos);
1854 }
1855
1856#if __cplusplus201402L >= 201103L
1857 /**
1858 * @brief Remove the last character.
1859 *
1860 * The string must be non-empty.
1861 */
1862 void
1863 pop_back() noexcept
1864 {
1865 __glibcxx_assert(!empty());
1866 _M_erase(size() - 1, 1);
1867 }
1868#endif // C++11
1869
1870 /**
1871 * @brief Replace characters with value from another string.
1872 * @param __pos Index of first character to replace.
1873 * @param __n Number of characters to be replaced.
1874 * @param __str String to insert.
1875 * @return Reference to this string.
1876 * @throw std::out_of_range If @a pos is beyond the end of this
1877 * string.
1878 * @throw std::length_error If new length exceeds @c max_size().
1879 *
1880 * Removes the characters in the range [__pos,__pos+__n) from
1881 * this string. In place, the value of @a __str is inserted.
1882 * If @a __pos is beyond end of string, out_of_range is thrown.
1883 * If the length of the result exceeds max_size(), length_error
1884 * is thrown. The value of the string doesn't change if an
1885 * error is thrown.
1886 */
1887 basic_string&
1888 replace(size_type __pos, size_type __n, const basic_string& __str)
1889 { return this->replace(__pos, __n, __str._M_data(), __str.size()); }
1890
1891 /**
1892 * @brief Replace characters with value from another string.
1893 * @param __pos1 Index of first character to replace.
1894 * @param __n1 Number of characters to be replaced.
1895 * @param __str String to insert.
1896 * @param __pos2 Index of first character of str to use.
1897 * @param __n2 Number of characters from str to use.
1898 * @return Reference to this string.
1899 * @throw std::out_of_range If @a __pos1 > size() or @a __pos2 >
1900 * __str.size().
1901 * @throw std::length_error If new length exceeds @c max_size().
1902 *
1903 * Removes the characters in the range [__pos1,__pos1 + n) from this
1904 * string. In place, the value of @a __str is inserted. If @a __pos is
1905 * beyond end of string, out_of_range is thrown. If the length of the
1906 * result exceeds max_size(), length_error is thrown. The value of the
1907 * string doesn't change if an error is thrown.
1908 */
1909 basic_string&
1910 replace(size_type __pos1, size_type __n1, const basic_string& __str,
1911 size_type __pos2, size_type __n2 = npos)
1912 { return this->replace(__pos1, __n1, __str._M_data()
1913 + __str._M_check(__pos2, "basic_string::replace"),
1914 __str._M_limit(__pos2, __n2)); }
1915
1916 /**
1917 * @brief Replace characters with value of a C substring.
1918 * @param __pos Index of first character to replace.
1919 * @param __n1 Number of characters to be replaced.
1920 * @param __s C string to insert.
1921 * @param __n2 Number of characters from @a s to use.
1922 * @return Reference to this string.
1923 * @throw std::out_of_range If @a pos1 > size().
1924 * @throw std::length_error If new length exceeds @c max_size().
1925 *
1926 * Removes the characters in the range [__pos,__pos + __n1)
1927 * from this string. In place, the first @a __n2 characters of
1928 * @a __s are inserted, or all of @a __s if @a __n2 is too large. If
1929 * @a __pos is beyond end of string, out_of_range is thrown. If
1930 * the length of result exceeds max_size(), length_error is
1931 * thrown. The value of the string doesn't change if an error
1932 * is thrown.
1933 */
1934 basic_string&
1935 replace(size_type __pos, size_type __n1, const _CharT* __s,
1936 size_type __n2)
1937 {
1938 __glibcxx_requires_string_len(__s, __n2);
1939 return _M_replace(_M_check(__pos, "basic_string::replace"),
1940 _M_limit(__pos, __n1), __s, __n2);
1941 }
1942
1943 /**
1944 * @brief Replace characters with value of a C string.
1945 * @param __pos Index of first character to replace.
1946 * @param __n1 Number of characters to be replaced.
1947 * @param __s C string to insert.
1948 * @return Reference to this string.
1949 * @throw std::out_of_range If @a pos > size().
1950 * @throw std::length_error If new length exceeds @c max_size().
1951 *
1952 * Removes the characters in the range [__pos,__pos + __n1)
1953 * from this string. In place, the characters of @a __s are
1954 * inserted. If @a __pos is beyond end of string, out_of_range
1955 * is thrown. If the length of result exceeds max_size(),
1956 * length_error is thrown. The value of the string doesn't
1957 * change if an error is thrown.
1958 */
1959 basic_string&
1960 replace(size_type __pos, size_type __n1, const _CharT* __s)
1961 {
1962 __glibcxx_requires_string(__s);
1963 return this->replace(__pos, __n1, __s, traits_type::length(__s));
1964 }
1965
1966 /**
1967 * @brief Replace characters with multiple characters.
1968 * @param __pos Index of first character to replace.
1969 * @param __n1 Number of characters to be replaced.
1970 * @param __n2 Number of characters to insert.
1971 * @param __c Character to insert.
1972 * @return Reference to this string.
1973 * @throw std::out_of_range If @a __pos > size().
1974 * @throw std::length_error If new length exceeds @c max_size().
1975 *
1976 * Removes the characters in the range [pos,pos + n1) from this
1977 * string. In place, @a __n2 copies of @a __c are inserted.
1978 * If @a __pos is beyond end of string, out_of_range is thrown.
1979 * If the length of result exceeds max_size(), length_error is
1980 * thrown. The value of the string doesn't change if an error
1981 * is thrown.
1982 */
1983 basic_string&
1984 replace(size_type __pos, size_type __n1, size_type __n2, _CharT __c)
1985 { return _M_replace_aux(_M_check(__pos, "basic_string::replace"),
1986 _M_limit(__pos, __n1), __n2, __c); }
1987
1988 /**
1989 * @brief Replace range of characters with string.
1990 * @param __i1 Iterator referencing start of range to replace.
1991 * @param __i2 Iterator referencing end of range to replace.
1992 * @param __str String value to insert.
1993 * @return Reference to this string.
1994 * @throw std::length_error If new length exceeds @c max_size().
1995 *
1996 * Removes the characters in the range [__i1,__i2). In place,
1997 * the value of @a __str is inserted. If the length of result
1998 * exceeds max_size(), length_error is thrown. The value of
1999 * the string doesn't change if an error is thrown.
2000 */
2001 basic_string&
2002 replace(__const_iterator __i1, __const_iterator __i2,
2003 const basic_string& __str)
2004 { return this->replace(__i1, __i2, __str._M_data(), __str.size()); }
2005
2006 /**
2007 * @brief Replace range of characters with C substring.
2008 * @param __i1 Iterator referencing start of range to replace.
2009 * @param __i2 Iterator referencing end of range to replace.
2010 * @param __s C string value to insert.
2011 * @param __n Number of characters from s to insert.
2012 * @return Reference to this string.
2013 * @throw std::length_error If new length exceeds @c max_size().
2014 *
2015 * Removes the characters in the range [__i1,__i2). In place,
2016 * the first @a __n characters of @a __s are inserted. If the
2017 * length of result exceeds max_size(), length_error is thrown.
2018 * The value of the string doesn't change if an error is
2019 * thrown.
2020 */
2021 basic_string&
2022 replace(__const_iterator __i1, __const_iterator __i2,
2023 const _CharT* __s, size_type __n)
2024 {
2025 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2026 && __i2 <= end());
2027 return this->replace(__i1 - begin(), __i2 - __i1, __s, __n);
2028 }
2029
2030 /**
2031 * @brief Replace range of characters with C string.
2032 * @param __i1 Iterator referencing start of range to replace.
2033 * @param __i2 Iterator referencing end of range to replace.
2034 * @param __s C string value to insert.
2035 * @return Reference to this string.
2036 * @throw std::length_error If new length exceeds @c max_size().
2037 *
2038 * Removes the characters in the range [__i1,__i2). In place,
2039 * the characters of @a __s are inserted. If the length of
2040 * result exceeds max_size(), length_error is thrown. The
2041 * value of the string doesn't change if an error is thrown.
2042 */
2043 basic_string&
2044 replace(__const_iterator __i1, __const_iterator __i2, const _CharT* __s)
2045 {
2046 __glibcxx_requires_string(__s);
2047 return this->replace(__i1, __i2, __s, traits_type::length(__s));
2048 }
2049
2050 /**
2051 * @brief Replace range of characters with multiple characters
2052 * @param __i1 Iterator referencing start of range to replace.
2053 * @param __i2 Iterator referencing end of range to replace.
2054 * @param __n Number of characters to insert.
2055 * @param __c Character to insert.
2056 * @return Reference to this string.
2057 * @throw std::length_error If new length exceeds @c max_size().
2058 *
2059 * Removes the characters in the range [__i1,__i2). In place,
2060 * @a __n copies of @a __c are inserted. If the length of
2061 * result exceeds max_size(), length_error is thrown. The
2062 * value of the string doesn't change if an error is thrown.
2063 */
2064 basic_string&
2065 replace(__const_iterator __i1, __const_iterator __i2, size_type __n,
2066 _CharT __c)
2067 {
2068 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2069 && __i2 <= end());
2070 return _M_replace_aux(__i1 - begin(), __i2 - __i1, __n, __c);
2071 }
2072
2073 /**
2074 * @brief Replace range of characters with range.
2075 * @param __i1 Iterator referencing start of range to replace.
2076 * @param __i2 Iterator referencing end of range to replace.
2077 * @param __k1 Iterator referencing start of range to insert.
2078 * @param __k2 Iterator referencing end of range to insert.
2079 * @return Reference to this string.
2080 * @throw std::length_error If new length exceeds @c max_size().
2081 *
2082 * Removes the characters in the range [__i1,__i2). In place,
2083 * characters in the range [__k1,__k2) are inserted. If the
2084 * length of result exceeds max_size(), length_error is thrown.
2085 * The value of the string doesn't change if an error is
2086 * thrown.
2087 */
2088#if __cplusplus201402L >= 201103L
2089 template<class _InputIterator,
2090 typename = std::_RequireInputIter<_InputIterator>>
2091 basic_string&
2092 replace(const_iterator __i1, const_iterator __i2,
2093 _InputIterator __k1, _InputIterator __k2)
2094 {
2095 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2096 && __i2 <= end());
2097 __glibcxx_requires_valid_range(__k1, __k2);
2098 return this->_M_replace_dispatch(__i1, __i2, __k1, __k2,
2099 std::__false_type());
2100 }
2101#else
2102 template<class _InputIterator>
2103#ifdef _GLIBCXX_DISAMBIGUATE_REPLACE_INST
2104 typename __enable_if_not_native_iterator<_InputIterator>::__type
2105#else
2106 basic_string&
2107#endif
2108 replace(iterator __i1, iterator __i2,
2109 _InputIterator __k1, _InputIterator __k2)
2110 {
2111 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2112 && __i2 <= end());
2113 __glibcxx_requires_valid_range(__k1, __k2);
2114 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
2115 return _M_replace_dispatch(__i1, __i2, __k1, __k2, _Integral());
2116 }
2117#endif
2118
2119 // Specializations for the common case of pointer and iterator:
2120 // useful to avoid the overhead of temporary buffering in _M_replace.
2121 basic_string&
2122 replace(__const_iterator __i1, __const_iterator __i2,
2123 _CharT* __k1, _CharT* __k2)
2124 {
2125 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2126 && __i2 <= end());
2127 __glibcxx_requires_valid_range(__k1, __k2);
2128 return this->replace(__i1 - begin(), __i2 - __i1,
2129 __k1, __k2 - __k1);
2130 }
2131
2132 basic_string&
2133 replace(__const_iterator __i1, __const_iterator __i2,
2134 const _CharT* __k1, const _CharT* __k2)
2135 {
2136 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2137 && __i2 <= end());
2138 __glibcxx_requires_valid_range(__k1, __k2);
2139 return this->replace(__i1 - begin(), __i2 - __i1,
2140 __k1, __k2 - __k1);
2141 }
2142
2143 basic_string&
2144 replace(__const_iterator __i1, __const_iterator __i2,
2145 iterator __k1, iterator __k2)
2146 {
2147 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2148 && __i2 <= end());
2149 __glibcxx_requires_valid_range(__k1, __k2);
2150 return this->replace(__i1 - begin(), __i2 - __i1,
2151 __k1.base(), __k2 - __k1);
2152 }
2153
2154 basic_string&
2155 replace(__const_iterator __i1, __const_iterator __i2,
2156 const_iterator __k1, const_iterator __k2)
2157 {
2158 _GLIBCXX_DEBUG_PEDASSERT(begin() <= __i1 && __i1 <= __i2
2159 && __i2 <= end());
2160 __glibcxx_requires_valid_range(__k1, __k2);
2161 return this->replace(__i1 - begin(), __i2 - __i1,
2162 __k1.base(), __k2 - __k1);
2163 }
2164
2165#if __cplusplus201402L >= 201103L
2166 /**
2167 * @brief Replace range of characters with initializer_list.
2168 * @param __i1 Iterator referencing start of range to replace.
2169 * @param __i2 Iterator referencing end of range to replace.
2170 * @param __l The initializer_list of characters to insert.
2171 * @return Reference to this string.
2172 * @throw std::length_error If new length exceeds @c max_size().
2173 *
2174 * Removes the characters in the range [__i1,__i2). In place,
2175 * characters in the range [__k1,__k2) are inserted. If the
2176 * length of result exceeds max_size(), length_error is thrown.
2177 * The value of the string doesn't change if an error is
2178 * thrown.
2179 */
2180 basic_string& replace(const_iterator __i1, const_iterator __i2,
2181 initializer_list<_CharT> __l)
2182 { return this->replace(__i1, __i2, __l.begin(), __l.size()); }
2183#endif // C++11
2184
2185#if __cplusplus201402L >= 201703L
2186 /**
2187 * @brief Replace range of characters with string_view.
2188 * @param __pos The position to replace at.
2189 * @param __n The number of characters to replace.
2190 * @param __svt The object convertible to string_view to insert.
2191 * @return Reference to this string.
2192 */
2193 template<typename _Tp>
2194 _If_sv<_Tp, basic_string&>
2195 replace(size_type __pos, size_type __n, const _Tp& __svt)
2196 {
2197 __sv_type __sv = __svt;
2198 return this->replace(__pos, __n, __sv.data(), __sv.size());
2199 }
2200
2201 /**
2202 * @brief Replace range of characters with string_view.
2203 * @param __pos1 The position to replace at.
2204 * @param __n1 The number of characters to replace.
2205 * @param __svt The object convertible to string_view to insert from.
2206 * @param __pos2 The position in the string_view to insert from.
2207 * @param __n2 The number of characters to insert.
2208 * @return Reference to this string.
2209 */
2210 template<typename _Tp>
2211 _If_sv<_Tp, basic_string&>
2212 replace(size_type __pos1, size_type __n1, const _Tp& __svt,
2213 size_type __pos2, size_type __n2 = npos)
2214 {
2215 __sv_type __sv = __svt;
2216 return this->replace(__pos1, __n1,
2217 __sv.data()
2218 + std::__sv_check(__sv.size(), __pos2, "basic_string::replace"),
2219 std::__sv_limit(__sv.size(), __pos2, __n2));
2220 }
2221
2222 /**
2223 * @brief Replace range of characters with string_view.
2224 * @param __i1 An iterator referencing the start position
2225 to replace at.
2226 * @param __i2 An iterator referencing the end position
2227 for the replace.
2228 * @param __svt The object convertible to string_view to insert from.
2229 * @return Reference to this string.
2230 */
2231 template<typename _Tp>
2232 _If_sv<_Tp, basic_string&>
2233 replace(const_iterator __i1, const_iterator __i2, const _Tp& __svt)
2234 {
2235 __sv_type __sv = __svt;
2236 return this->replace(__i1 - begin(), __i2 - __i1, __sv);
2237 }
2238#endif // C++17
2239
2240 private:
2241 template<class _Integer>
2242 basic_string&
2243 _M_replace_dispatch(const_iterator __i1, const_iterator __i2,
2244 _Integer __n, _Integer __val, __true_type)
2245 { return _M_replace_aux(__i1 - begin(), __i2 - __i1, __n, __val); }
2246
2247 template<class _InputIterator>
2248 basic_string&
2249 _M_replace_dispatch(const_iterator __i1, const_iterator __i2,
2250 _InputIterator __k1, _InputIterator __k2,
2251 __false_type);
2252
2253 basic_string&
2254 _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
2255 _CharT __c);
2256
2257 basic_string&
2258 _M_replace(size_type __pos, size_type __len1, const _CharT* __s,
2259 const size_type __len2);
2260
2261 basic_string&
2262 _M_append(const _CharT* __s, size_type __n);
2263
2264 public:
2265
2266 /**
2267 * @brief Copy substring into C string.
2268 * @param __s C string to copy value into.
2269 * @param __n Number of characters to copy.
2270 * @param __pos Index of first character to copy.
2271 * @return Number of characters actually copied
2272 * @throw std::out_of_range If __pos > size().
2273 *
2274 * Copies up to @a __n characters starting at @a __pos into the
2275 * C string @a __s. If @a __pos is %greater than size(),
2276 * out_of_range is thrown.
2277 */
2278 size_type
2279 copy(_CharT* __s, size_type __n, size_type __pos = 0) const;
2280
2281 /**
2282 * @brief Swap contents with another string.
2283 * @param __s String to swap with.
2284 *
2285 * Exchanges the contents of this string with that of @a __s in constant
2286 * time.
2287 */
2288 void
2289 swap(basic_string& __s) _GLIBCXX_NOEXCEPTnoexcept;
2290
2291 // String operations:
2292 /**
2293 * @brief Return const pointer to null-terminated contents.
2294 *
2295 * This is a handle to internal data. Do not modify or dire things may
2296 * happen.
2297 */
2298 const _CharT*
2299 c_str() const _GLIBCXX_NOEXCEPTnoexcept
2300 { return _M_data(); }
2301
2302 /**
2303 * @brief Return const pointer to contents.
2304 *
2305 * This is a pointer to internal data. It is undefined to modify
2306 * the contents through the returned pointer. To get a pointer that
2307 * allows modifying the contents use @c &str[0] instead,
2308 * (or in C++17 the non-const @c str.data() overload).
2309 */
2310 const _CharT*
2311 data() const _GLIBCXX_NOEXCEPTnoexcept
2312 { return _M_data(); }
2313
2314#if __cplusplus201402L >= 201703L
2315 /**
2316 * @brief Return non-const pointer to contents.
2317 *
2318 * This is a pointer to the character sequence held by the string.
2319 * Modifying the characters in the sequence is allowed.
2320 */
2321 _CharT*
2322 data() noexcept
2323 { return _M_data(); }
2324#endif
2325
2326 /**
2327 * @brief Return copy of allocator used to construct this string.
2328 */
2329 allocator_type
2330 get_allocator() const _GLIBCXX_NOEXCEPTnoexcept
2331 { return _M_get_allocator(); }
2332
2333 /**
2334 * @brief Find position of a C substring.
2335 * @param __s C string to locate.
2336 * @param __pos Index of character to search from.
2337 * @param __n Number of characters from @a s to search for.
2338 * @return Index of start of first occurrence.
2339 *
2340 * Starting from @a __pos, searches forward for the first @a
2341 * __n characters in @a __s within this string. If found,
2342 * returns the index where it begins. If not found, returns
2343 * npos.
2344 */
2345 size_type
2346 find(const _CharT* __s, size_type __pos, size_type __n) const
2347 _GLIBCXX_NOEXCEPTnoexcept;
2348
2349 /**
2350 * @brief Find position of a string.
2351 * @param __str String to locate.
2352 * @param __pos Index of character to search from (default 0).
2353 * @return Index of start of first occurrence.
2354 *
2355 * Starting from @a __pos, searches forward for value of @a __str within
2356 * this string. If found, returns the index where it begins. If not
2357 * found, returns npos.
2358 */
2359 size_type
2360 find(const basic_string& __str, size_type __pos = 0) const
2361 _GLIBCXX_NOEXCEPTnoexcept
2362 { return this->find(__str.data(), __pos, __str.size()); }
2363
2364#if __cplusplus201402L >= 201703L
2365 /**
2366 * @brief Find position of a string_view.
2367 * @param __svt The object convertible to string_view to locate.
2368 * @param __pos Index of character to search from (default 0).
2369 * @return Index of start of first occurrence.
2370 */
2371 template<typename _Tp>
2372 _If_sv<_Tp, size_type>
2373 find(const _Tp& __svt, size_type __pos = 0) const
2374 noexcept(is_same<_Tp, __sv_type>::value)
2375 {
2376 __sv_type __sv = __svt;
2377 return this->find(__sv.data(), __pos, __sv.size());
2378 }
2379#endif // C++17
2380
2381 /**
2382 * @brief Find position of a C string.
2383 * @param __s C string to locate.
2384 * @param __pos Index of character to search from (default 0).
2385 * @return Index of start of first occurrence.
2386 *
2387 * Starting from @a __pos, searches forward for the value of @a
2388 * __s within this string. If found, returns the index where
2389 * it begins. If not found, returns npos.
2390 */
2391 size_type
2392 find(const _CharT* __s, size_type __pos = 0) const _GLIBCXX_NOEXCEPTnoexcept
2393 {
2394 __glibcxx_requires_string(__s);
2395 return this->find(__s, __pos, traits_type::length(__s));
2396 }
2397
2398 /**
2399 * @brief Find position of a character.
2400 * @param __c Character to locate.
2401 * @param __pos Index of character to search from (default 0).
2402 * @return Index of first occurrence.
2403 *
2404 * Starting from @a __pos, searches forward for @a __c within
2405 * this string. If found, returns the index where it was
2406 * found. If not found, returns npos.
2407 */
2408 size_type
2409 find(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPTnoexcept;
2410
2411 /**
2412 * @brief Find last position of a string.
2413 * @param __str String to locate.
2414 * @param __pos Index of character to search back from (default end).
2415 * @return Index of start of last occurrence.
2416 *
2417 * Starting from @a __pos, searches backward for value of @a
2418 * __str within this string. If found, returns the index where
2419 * it begins. If not found, returns npos.
2420 */
2421 size_type
2422 rfind(const basic_string& __str, size_type __pos = npos) const
2423 _GLIBCXX_NOEXCEPTnoexcept
2424 { return this->rfind(__str.data(), __pos, __str.size()); }
2425
2426#if __cplusplus201402L >= 201703L
2427 /**
2428 * @brief Find last position of a string_view.
2429 * @param __svt The object convertible to string_view to locate.
2430 * @param __pos Index of character to search back from (default end).
2431 * @return Index of start of last occurrence.
2432 */
2433 template<typename _Tp>
2434 _If_sv<_Tp, size_type>
2435 rfind(const _Tp& __svt, size_type __pos = npos) const
2436 noexcept(is_same<_Tp, __sv_type>::value)
2437 {
2438 __sv_type __sv = __svt;
2439 return this->rfind(__sv.data(), __pos, __sv.size());
2440 }
2441#endif // C++17
2442
2443 /**
2444 * @brief Find last position of a C substring.
2445 * @param __s C string to locate.
2446 * @param __pos Index of character to search back from.
2447 * @param __n Number of characters from s to search for.
2448 * @return Index of start of last occurrence.
2449 *
2450 * Starting from @a __pos, searches backward for the first @a
2451 * __n characters in @a __s within this string. If found,
2452 * returns the index where it begins. If not found, returns
2453 * npos.
2454 */
2455 size_type
2456 rfind(const _CharT* __s, size_type __pos, size_type __n) const
2457 _GLIBCXX_NOEXCEPTnoexcept;
2458
2459 /**
2460 * @brief Find last position of a C string.
2461 * @param __s C string to locate.
2462 * @param __pos Index of character to start search at (default end).
2463 * @return Index of start of last occurrence.
2464 *
2465 * Starting from @a __pos, searches backward for the value of
2466 * @a __s within this string. If found, returns the index
2467 * where it begins. If not found, returns npos.
2468 */
2469 size_type
2470 rfind(const _CharT* __s, size_type __pos = npos) const
2471 {
2472 __glibcxx_requires_string(__s);
2473 return this->rfind(__s, __pos, traits_type::length(__s));
2474 }
2475
2476 /**
2477 * @brief Find last position of a character.
2478 * @param __c Character to locate.
2479 * @param __pos Index of character to search back from (default end).
2480 * @return Index of last occurrence.
2481 *
2482 * Starting from @a __pos, searches backward for @a __c within
2483 * this string. If found, returns the index where it was
2484 * found. If not found, returns npos.
2485 */
2486 size_type
2487 rfind(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPTnoexcept;
2488
2489 /**
2490 * @brief Find position of a character of string.
2491 * @param __str String containing characters to locate.
2492 * @param __pos Index of character to search from (default 0).
2493 * @return Index of first occurrence.
2494 *
2495 * Starting from @a __pos, searches forward for one of the
2496 * characters of @a __str within this string. If found,
2497 * returns the index where it was found. If not found, returns
2498 * npos.
2499 */
2500 size_type
2501 find_first_of(const basic_string& __str, size_type __pos = 0) const
2502 _GLIBCXX_NOEXCEPTnoexcept
2503 { return this->find_first_of(__str.data(), __pos, __str.size()); }
2504
2505#if __cplusplus201402L >= 201703L
2506 /**
2507 * @brief Find position of a character of a string_view.
2508 * @param __svt An object convertible to string_view containing
2509 * characters to locate.
2510 * @param __pos Index of character to search from (default 0).
2511 * @return Index of first occurrence.
2512 */
2513 template<typename _Tp>
2514 _If_sv<_Tp, size_type>
2515 find_first_of(const _Tp& __svt, size_type __pos = 0) const
2516 noexcept(is_same<_Tp, __sv_type>::value)
2517 {
2518 __sv_type __sv = __svt;
2519 return this->find_first_of(__sv.data(), __pos, __sv.size());
2520 }
2521#endif // C++17
2522
2523 /**
2524 * @brief Find position of a character of C substring.
2525 * @param __s String containing characters to locate.
2526 * @param __pos Index of character to search from.
2527 * @param __n Number of characters from s to search for.
2528 * @return Index of first occurrence.
2529 *
2530 * Starting from @a __pos, searches forward for one of the
2531 * first @a __n characters of @a __s within this string. If
2532 * found, returns the index where it was found. If not found,
2533 * returns npos.
2534 */
2535 size_type
2536 find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
2537 _GLIBCXX_NOEXCEPTnoexcept;
2538
2539 /**
2540 * @brief Find position of a character of C string.
2541 * @param __s String containing characters to locate.
2542 * @param __pos Index of character to search from (default 0).
2543 * @return Index of first occurrence.
2544 *
2545 * Starting from @a __pos, searches forward for one of the
2546 * characters of @a __s within this string. If found, returns
2547 * the index where it was found. If not found, returns npos.
2548 */
2549 size_type
2550 find_first_of(const _CharT* __s, size_type __pos = 0) const
2551 _GLIBCXX_NOEXCEPTnoexcept
2552 {
2553 __glibcxx_requires_string(__s);
2554 return this->find_first_of(__s, __pos, traits_type::length(__s));
2555 }
2556
2557 /**
2558 * @brief Find position of a character.
2559 * @param __c Character to locate.
2560 * @param __pos Index of character to search from (default 0).
2561 * @return Index of first occurrence.
2562 *
2563 * Starting from @a __pos, searches forward for the character
2564 * @a __c within this string. If found, returns the index
2565 * where it was found. If not found, returns npos.
2566 *
2567 * Note: equivalent to find(__c, __pos).
2568 */
2569 size_type
2570 find_first_of(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPTnoexcept
2571 { return this->find(__c, __pos); }
2572
2573 /**
2574 * @brief Find last position of a character of string.
2575 * @param __str String containing characters to locate.
2576 * @param __pos Index of character to search back from (default end).
2577 * @return Index of last occurrence.
2578 *
2579 * Starting from @a __pos, searches backward for one of the
2580 * characters of @a __str within this string. If found,
2581 * returns the index where it was found. If not found, returns
2582 * npos.
2583 */
2584 size_type
2585 find_last_of(const basic_string& __str, size_type __pos = npos) const
2586 _GLIBCXX_NOEXCEPTnoexcept
2587 { return this->find_last_of(__str.data(), __pos, __str.size()); }
2588
2589#if __cplusplus201402L >= 201703L
2590 /**
2591 * @brief Find last position of a character of string.
2592 * @param __svt An object convertible to string_view containing
2593 * characters to locate.
2594 * @param __pos Index of character to search back from (default end).
2595 * @return Index of last occurrence.
2596 */
2597 template<typename _Tp>
2598 _If_sv<_Tp, size_type>
2599 find_last_of(const _Tp& __svt, size_type __pos = npos) const
2600 noexcept(is_same<_Tp, __sv_type>::value)
2601 {
2602 __sv_type __sv = __svt;
2603 return this->find_last_of(__sv.data(), __pos, __sv.size());
2604 }
2605#endif // C++17
2606
2607 /**
2608 * @brief Find last position of a character of C substring.
2609 * @param __s C string containing characters to locate.
2610 * @param __pos Index of character to search back from.
2611 * @param __n Number of characters from s to search for.
2612 * @return Index of last occurrence.
2613 *
2614 * Starting from @a __pos, searches backward for one of the
2615 * first @a __n characters of @a __s within this string. If
2616 * found, returns the index where it was found. If not found,
2617 * returns npos.
2618 */
2619 size_type
2620 find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
2621 _GLIBCXX_NOEXCEPTnoexcept;
2622
2623 /**
2624 * @brief Find last position of a character of C string.
2625 * @param __s C string containing characters to locate.
2626 * @param __pos Index of character to search back from (default end).
2627 * @return Index of last occurrence.
2628 *
2629 * Starting from @a __pos, searches backward for one of the
2630 * characters of @a __s within this string. If found, returns
2631 * the index where it was found. If not found, returns npos.
2632 */
2633 size_type
2634 find_last_of(const _CharT* __s, size_type __pos = npos) const
2635 _GLIBCXX_NOEXCEPTnoexcept
2636 {
2637 __glibcxx_requires_string(__s);
2638 return this->find_last_of(__s, __pos, traits_type::length(__s));
2639 }
2640
2641 /**
2642 * @brief Find last position of a character.
2643 * @param __c Character to locate.
2644 * @param __pos Index of character to search back from (default end).
2645 * @return Index of last occurrence.
2646 *
2647 * Starting from @a __pos, searches backward for @a __c within
2648 * this string. If found, returns the index where it was
2649 * found. If not found, returns npos.
2650 *
2651 * Note: equivalent to rfind(__c, __pos).
2652 */
2653 size_type
2654 find_last_of(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPTnoexcept
2655 { return this->rfind(__c, __pos); }
2656
2657 /**
2658 * @brief Find position of a character not in string.
2659 * @param __str String containing characters to avoid.
2660 * @param __pos Index of character to search from (default 0).
2661 * @return Index of first occurrence.
2662 *
2663 * Starting from @a __pos, searches forward for a character not contained
2664 * in @a __str within this string. If found, returns the index where it
2665 * was found. If not found, returns npos.
2666 */
2667 size_type
2668 find_first_not_of(const basic_string& __str, size_type __pos = 0) const
2669 _GLIBCXX_NOEXCEPTnoexcept
2670 { return this->find_first_not_of(__str.data(), __pos, __str.size()); }
2671
2672#if __cplusplus201402L >= 201703L
2673 /**
2674 * @brief Find position of a character not in a string_view.
2675 * @param __svt A object convertible to string_view containing
2676 * characters to avoid.
2677 * @param __pos Index of character to search from (default 0).
2678 * @return Index of first occurrence.
2679 */
2680 template<typename _Tp>
2681 _If_sv<_Tp, size_type>
2682 find_first_not_of(const _Tp& __svt, size_type __pos = 0) const
2683 noexcept(is_same<_Tp, __sv_type>::value)
2684 {
2685 __sv_type __sv = __svt;
2686 return this->find_first_not_of(__sv.data(), __pos, __sv.size());
2687 }
2688#endif // C++17
2689
2690 /**
2691 * @brief Find position of a character not in C substring.
2692 * @param __s C string containing characters to avoid.
2693 * @param __pos Index of character to search from.
2694 * @param __n Number of characters from __s to consider.
2695 * @return Index of first occurrence.
2696 *
2697 * Starting from @a __pos, searches forward for a character not
2698 * contained in the first @a __n characters of @a __s within
2699 * this string. If found, returns the index where it was
2700 * found. If not found, returns npos.
2701 */
2702 size_type
2703 find_first_not_of(const _CharT* __s, size_type __pos,
2704 size_type __n) const _GLIBCXX_NOEXCEPTnoexcept;
2705
2706 /**
2707 * @brief Find position of a character not in C string.
2708 * @param __s C string containing characters to avoid.
2709 * @param __pos Index of character to search from (default 0).
2710 * @return Index of first occurrence.
2711 *
2712 * Starting from @a __pos, searches forward for a character not
2713 * contained in @a __s within this string. If found, returns
2714 * the index where it was found. If not found, returns npos.
2715 */
2716 size_type
2717 find_first_not_of(const _CharT* __s, size_type __pos = 0) const
2718 _GLIBCXX_NOEXCEPTnoexcept
2719 {
2720 __glibcxx_requires_string(__s);
2721 return this->find_first_not_of(__s, __pos, traits_type::length(__s));
2722 }
2723
2724 /**
2725 * @brief Find position of a different character.
2726 * @param __c Character to avoid.
2727 * @param __pos Index of character to search from (default 0).
2728 * @return Index of first occurrence.
2729 *
2730 * Starting from @a __pos, searches forward for a character
2731 * other than @a __c within this string. If found, returns the
2732 * index where it was found. If not found, returns npos.
2733 */
2734 size_type
2735 find_first_not_of(_CharT __c, size_type __pos = 0) const
2736 _GLIBCXX_NOEXCEPTnoexcept;
2737
2738 /**
2739 * @brief Find last position of a character not in string.
2740 * @param __str String containing characters to avoid.
2741 * @param __pos Index of character to search back from (default end).
2742 * @return Index of last occurrence.
2743 *
2744 * Starting from @a __pos, searches backward for a character
2745 * not contained in @a __str within this string. If found,
2746 * returns the index where it was found. If not found, returns
2747 * npos.
2748 */
2749 size_type
2750 find_last_not_of(const basic_string& __str, size_type __pos = npos) const
2751 _GLIBCXX_NOEXCEPTnoexcept
2752 { return this->find_last_not_of(__str.data(), __pos, __str.size()); }
2753
2754#if __cplusplus201402L >= 201703L
2755 /**
2756 * @brief Find last position of a character not in a string_view.
2757 * @param __svt An object convertible to string_view containing
2758 * characters to avoid.
2759 * @param __pos Index of character to search back from (default end).
2760 * @return Index of last occurrence.
2761 */
2762 template<typename _Tp>
2763 _If_sv<_Tp, size_type>
2764 find_last_not_of(const _Tp& __svt, size_type __pos = npos) const
2765 noexcept(is_same<_Tp, __sv_type>::value)
2766 {
2767 __sv_type __sv = __svt;
2768 return this->find_last_not_of(__sv.data(), __pos, __sv.size());
2769 }
2770#endif // C++17
2771
2772 /**
2773 * @brief Find last position of a character not in C substring.
2774 * @param __s C string containing characters to avoid.
2775 * @param __pos Index of character to search back from.
2776 * @param __n Number of characters from s to consider.
2777 * @return Index of last occurrence.
2778 *
2779 * Starting from @a __pos, searches backward for a character not
2780 * contained in the first @a __n characters of @a __s within this string.
2781 * If found, returns the index where it was found. If not found,
2782 * returns npos.
2783 */
2784 size_type
2785 find_last_not_of(const _CharT* __s, size_type __pos,
2786 size_type __n) const _GLIBCXX_NOEXCEPTnoexcept;
2787 /**
2788 * @brief Find last position of a character not in C string.
2789 * @param __s C string containing characters to avoid.
2790 * @param __pos Index of character to search back from (default end).
2791 * @return Index of last occurrence.
2792 *
2793 * Starting from @a __pos, searches backward for a character
2794 * not contained in @a __s within this string. If found,
2795 * returns the index where it was found. If not found, returns
2796 * npos.
2797 */
2798 size_type
2799 find_last_not_of(const _CharT* __s, size_type __pos = npos) const
2800 _GLIBCXX_NOEXCEPTnoexcept
2801 {
2802 __glibcxx_requires_string(__s);
2803 return this->find_last_not_of(__s, __pos, traits_type::length(__s));
2804 }
2805
2806 /**
2807 * @brief Find last position of a different character.
2808 * @param __c Character to avoid.
2809 * @param __pos Index of character to search back from (default end).
2810 * @return Index of last occurrence.
2811 *
2812 * Starting from @a __pos, searches backward for a character other than
2813 * @a __c within this string. If found, returns the index where it was
2814 * found. If not found, returns npos.
2815 */
2816 size_type
2817 find_last_not_of(_CharT __c, size_type __pos = npos) const
2818 _GLIBCXX_NOEXCEPTnoexcept;
2819
2820 /**
2821 * @brief Get a substring.
2822 * @param __pos Index of first character (default 0).
2823 * @param __n Number of characters in substring (default remainder).
2824 * @return The new string.
2825 * @throw std::out_of_range If __pos > size().
2826 *
2827 * Construct and return a new string using the @a __n
2828 * characters starting at @a __pos. If the string is too
2829 * short, use the remainder of the characters. If @a __pos is
2830 * beyond the end of the string, out_of_range is thrown.
2831 */
2832 basic_string
2833 substr(size_type __pos = 0, size_type __n = npos) const
2834 { return basic_string(*this,
2835 _M_check(__pos, "basic_string::substr"), __n); }
2836
2837 /**
2838 * @brief Compare to a string.
2839 * @param __str String to compare against.
2840 * @return Integer < 0, 0, or > 0.
2841 *
2842 * Returns an integer < 0 if this string is ordered before @a
2843 * __str, 0 if their values are equivalent, or > 0 if this
2844 * string is ordered after @a __str. Determines the effective
2845 * length rlen of the strings to compare as the smallest of
2846 * size() and str.size(). The function then compares the two
2847 * strings by calling traits::compare(data(), str.data(),rlen).
2848 * If the result of the comparison is nonzero returns it,
2849 * otherwise the shorter one is ordered first.
2850 */
2851 int
2852 compare(const basic_string& __str) const
2853 {
2854 const size_type __size = this->size();
2855 const size_type __osize = __str.size();
2856 const size_type __len = std::min(__size, __osize);
2857
2858 int __r = traits_type::compare(_M_data(), __str.data(), __len);
2859 if (!__r)
2860 __r = _S_compare(__size, __osize);
2861 return __r;
2862 }
2863
2864#if __cplusplus201402L >= 201703L
2865 /**
2866 * @brief Compare to a string_view.
2867 * @param __svt An object convertible to string_view to compare against.
2868 * @return Integer < 0, 0, or > 0.
2869 */
2870 template<typename _Tp>
2871 _If_sv<_Tp, int>
2872 compare(const _Tp& __svt) const
2873 noexcept(is_same<_Tp, __sv_type>::value)
2874 {
2875 __sv_type __sv = __svt;
2876 const size_type __size = this->size();
2877 const size_type __osize = __sv.size();
2878 const size_type __len = std::min(__size, __osize);
2879
2880 int __r = traits_type::compare(_M_data(), __sv.data(), __len);
2881 if (!__r)
2882 __r = _S_compare(__size, __osize);
2883 return __r;
2884 }
2885
2886 /**
2887 * @brief Compare to a string_view.
2888 * @param __pos A position in the string to start comparing from.
2889 * @param __n The number of characters to compare.
2890 * @param __svt An object convertible to string_view to compare
2891 * against.
2892 * @return Integer < 0, 0, or > 0.
2893 */
2894 template<typename _Tp>
2895 _If_sv<_Tp, int>
2896 compare(size_type __pos, size_type __n, const _Tp& __svt) const
2897 noexcept(is_same<_Tp, __sv_type>::value)
2898 {
2899 __sv_type __sv = __svt;
2900 return __sv_type(*this).substr(__pos, __n).compare(__sv);
2901 }
2902
2903 /**
2904 * @brief Compare to a string_view.
2905 * @param __pos1 A position in the string to start comparing from.
2906 * @param __n1 The number of characters to compare.
2907 * @param __svt An object convertible to string_view to compare
2908 * against.
2909 * @param __pos2 A position in the string_view to start comparing from.
2910 * @param __n2 The number of characters to compare.
2911 * @return Integer < 0, 0, or > 0.
2912 */
2913 template<typename _Tp>
2914 _If_sv<_Tp, int>
2915 compare(size_type __pos1, size_type __n1, const _Tp& __svt,
2916 size_type __pos2, size_type __n2 = npos) const
2917 noexcept(is_same<_Tp, __sv_type>::value)
2918 {
2919 __sv_type __sv = __svt;
2920 return __sv_type(*this)
2921 .substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
2922 }
2923#endif // C++17
2924
2925 /**
2926 * @brief Compare substring to a string.
2927 * @param __pos Index of first character of substring.
2928 * @param __n Number of characters in substring.
2929 * @param __str String to compare against.
2930 * @return Integer < 0, 0, or > 0.
2931 *
2932 * Form the substring of this string from the @a __n characters
2933 * starting at @a __pos. Returns an integer < 0 if the
2934 * substring is ordered before @a __str, 0 if their values are
2935 * equivalent, or > 0 if the substring is ordered after @a
2936 * __str. Determines the effective length rlen of the strings
2937 * to compare as the smallest of the length of the substring
2938 * and @a __str.size(). The function then compares the two
2939 * strings by calling
2940 * traits::compare(substring.data(),str.data(),rlen). If the
2941 * result of the comparison is nonzero returns it, otherwise
2942 * the shorter one is ordered first.
2943 */
2944 int
2945 compare(size_type __pos, size_type __n, const basic_string& __str) const;
2946
2947 /**
2948 * @brief Compare substring to a substring.
2949 * @param __pos1 Index of first character of substring.
2950 * @param __n1 Number of characters in substring.
2951 * @param __str String to compare against.
2952 * @param __pos2 Index of first character of substring of str.
2953 * @param __n2 Number of characters in substring of str.
2954 * @return Integer < 0, 0, or > 0.
2955 *
2956 * Form the substring of this string from the @a __n1
2957 * characters starting at @a __pos1. Form the substring of @a
2958 * __str from the @a __n2 characters starting at @a __pos2.
2959 * Returns an integer < 0 if this substring is ordered before
2960 * the substring of @a __str, 0 if their values are equivalent,
2961 * or > 0 if this substring is ordered after the substring of
2962 * @a __str. Determines the effective length rlen of the
2963 * strings to compare as the smallest of the lengths of the
2964 * substrings. The function then compares the two strings by
2965 * calling
2966 * traits::compare(substring.data(),str.substr(pos2,n2).data(),rlen).
2967 * If the result of the comparison is nonzero returns it,
2968 * otherwise the shorter one is ordered first.
2969 */
2970 int
2971 compare(size_type __pos1, size_type __n1, const basic_string& __str,
2972 size_type __pos2, size_type __n2 = npos) const;
2973
2974 /**
2975 * @brief Compare to a C string.
2976 * @param __s C string to compare against.
2977 * @return Integer < 0, 0, or > 0.
2978 *
2979 * Returns an integer < 0 if this string is ordered before @a __s, 0 if
2980 * their values are equivalent, or > 0 if this string is ordered after
2981 * @a __s. Determines the effective length rlen of the strings to
2982 * compare as the smallest of size() and the length of a string
2983 * constructed from @a __s. The function then compares the two strings
2984 * by calling traits::compare(data(),s,rlen). If the result of the
2985 * comparison is nonzero returns it, otherwise the shorter one is
2986 * ordered first.
2987 */
2988 int
2989 compare(const _CharT* __s) const _GLIBCXX_NOEXCEPTnoexcept;
2990
2991 // _GLIBCXX_RESOLVE_LIB_DEFECTS
2992 // 5 String::compare specification questionable
2993 /**
2994 * @brief Compare substring to a C string.
2995 * @param __pos Index of first character of substring.
2996 * @param __n1 Number of characters in substring.
2997 * @param __s C string to compare against.
2998 * @return Integer < 0, 0, or > 0.
2999 *
3000 * Form the substring of this string from the @a __n1
3001 * characters starting at @a pos. Returns an integer < 0 if
3002 * the substring is ordered before @a __s, 0 if their values
3003 * are equivalent, or > 0 if the substring is ordered after @a
3004 * __s. Determines the effective length rlen of the strings to
3005 * compare as the smallest of the length of the substring and
3006 * the length of a string constructed from @a __s. The
3007 * function then compares the two string by calling
3008 * traits::compare(substring.data(),__s,rlen). If the result of
3009 * the comparison is nonzero returns it, otherwise the shorter
3010 * one is ordered first.
3011 */
3012 int
3013 compare(size_type __pos, size_type __n1, const _CharT* __s) const;
3014
3015 /**
3016 * @brief Compare substring against a character %array.
3017 * @param __pos Index of first character of substring.
3018 * @param __n1 Number of characters in substring.
3019 * @param __s character %array to compare against.
3020 * @param __n2 Number of characters of s.
3021 * @return Integer < 0, 0, or > 0.
3022 *
3023 * Form the substring of this string from the @a __n1
3024 * characters starting at @a __pos. Form a string from the
3025 * first @a __n2 characters of @a __s. Returns an integer < 0
3026 * if this substring is ordered before the string from @a __s,
3027 * 0 if their values are equivalent, or > 0 if this substring
3028 * is ordered after the string from @a __s. Determines the
3029 * effective length rlen of the strings to compare as the
3030 * smallest of the length of the substring and @a __n2. The
3031 * function then compares the two strings by calling
3032 * traits::compare(substring.data(),s,rlen). If the result of
3033 * the comparison is nonzero returns it, otherwise the shorter
3034 * one is ordered first.
3035 *
3036 * NB: s must have at least n2 characters, &apos;\\0&apos; has
3037 * no special meaning.
3038 */
3039 int
3040 compare(size_type __pos, size_type __n1, const _CharT* __s,
3041 size_type __n2) const;
3042
3043#if __cplusplus201402L > 201703L
3044 bool
3045 starts_with(basic_string_view<_CharT, _Traits> __x) const noexcept
3046 { return __sv_type(this->data(), this->size()).starts_with(__x); }
3047
3048 bool
3049 starts_with(_CharT __x) const noexcept
3050 { return __sv_type(this->data(), this->size()).starts_with(__x); }
3051
3052 bool
3053 starts_with(const _CharT* __x) const noexcept
3054 { return __sv_type(this->data(), this->size()).starts_with(__x); }
3055
3056 bool
3057 ends_with(basic_string_view<_CharT, _Traits> __x) const noexcept
3058 { return __sv_type(this->data(), this->size()).ends_with(__x); }
3059
3060 bool
3061 ends_with(_CharT __x) const noexcept
3062 { return __sv_type(this->data(), this->size()).ends_with(__x); }
3063
3064 bool
3065 ends_with(const _CharT* __x) const noexcept
3066 { return __sv_type(this->data(), this->size()).ends_with(__x); }
3067#endif // C++20
3068
3069 // Allow basic_stringbuf::__xfer_bufptrs to call _M_length:
3070 template<typename, typename, typename> friend class basic_stringbuf;
3071 };
3072_GLIBCXX_END_NAMESPACE_CXX11}
3073#else // !_GLIBCXX_USE_CXX11_ABI
3074 // Reference-counted COW string implentation
3075
3076 /**
3077 * @class basic_string basic_string.h <string>
3078 * @brief Managing sequences of characters and character-like objects.
3079 *
3080 * @ingroup strings
3081 * @ingroup sequences
3082 *
3083 * @tparam _CharT Type of character
3084 * @tparam _Traits Traits for character type, defaults to
3085 * char_traits<_CharT>.
3086 * @tparam _Alloc Allocator type, defaults to allocator<_CharT>.
3087 *
3088 * Meets the requirements of a <a href="tables.html#65">container</a>, a
3089 * <a href="tables.html#66">reversible container</a>, and a
3090 * <a href="tables.html#67">sequence</a>. Of the
3091 * <a href="tables.html#68">optional sequence requirements</a>, only
3092 * @c push_back, @c at, and @c %array access are supported.
3093 *
3094 * @doctodo
3095 *
3096 *
3097 * Documentation? What's that?
3098 * Nathan Myers <ncm@cantrip.org>.
3099 *
3100 * A string looks like this:
3101 *
3102 * @code
3103 * [_Rep]
3104 * _M_length
3105 * [basic_string<char_type>] _M_capacity
3106 * _M_dataplus _M_refcount
3107 * _M_p ----------------> unnamed array of char_type
3108 * @endcode
3109 *
3110 * Where the _M_p points to the first character in the string, and
3111 * you cast it to a pointer-to-_Rep and subtract 1 to get a
3112 * pointer to the header.
3113 *
3114 * This approach has the enormous advantage that a string object
3115 * requires only one allocation. All the ugliness is confined
3116 * within a single %pair of inline functions, which each compile to
3117 * a single @a add instruction: _Rep::_M_data(), and
3118 * string::_M_rep(); and the allocation function which gets a
3119 * block of raw bytes and with room enough and constructs a _Rep
3120 * object at the front.
3121 *
3122 * The reason you want _M_data pointing to the character %array and
3123 * not the _Rep is so that the debugger can see the string
3124 * contents. (Probably we should add a non-inline member to get
3125 * the _Rep for the debugger to use, so users can check the actual
3126 * string length.)
3127 *
3128 * Note that the _Rep object is a POD so that you can have a
3129 * static <em>empty string</em> _Rep object already @a constructed before
3130 * static constructors have run. The reference-count encoding is
3131 * chosen so that a 0 indicates one reference, so you never try to
3132 * destroy the empty-string _Rep object.
3133 *
3134 * All but the last paragraph is considered pretty conventional
3135 * for a C++ string implementation.
3136 */
3137 // 21.3 Template class basic_string
3138 template<typename _CharT, typename _Traits, typename _Alloc>
3139 class basic_string
3140 {
3141 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
3142 rebind<_CharT>::other _CharT_alloc_type;
3143 typedef __gnu_cxx::__alloc_traits<_CharT_alloc_type> _CharT_alloc_traits;
3144
3145 // Types:
3146 public:
3147 typedef _Traits traits_type;
3148 typedef typename _Traits::char_type value_type;
3149 typedef _Alloc allocator_type;
3150 typedef typename _CharT_alloc_type::size_type size_type;
3151 typedef typename _CharT_alloc_type::difference_type difference_type;
3152#if __cplusplus201402L < 201103L
3153 typedef typename _CharT_alloc_type::reference reference;
3154 typedef typename _CharT_alloc_type::const_reference const_reference;
3155#else
3156 typedef value_type& reference;
3157 typedef const value_type& const_reference;
3158#endif
3159 typedef typename _CharT_alloc_traits::pointer pointer;
3160 typedef typename _CharT_alloc_traits::const_pointer const_pointer;
3161 typedef __gnu_cxx::__normal_iterator<pointer, basic_string> iterator;
3162 typedef __gnu_cxx::__normal_iterator<const_pointer, basic_string>
3163 const_iterator;
3164 typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
3165 typedef std::reverse_iterator<iterator> reverse_iterator;
3166
3167 protected:
3168 // type used for positions in insert, erase etc.
3169 typedef iterator __const_iterator;
3170
3171 private:
3172 // _Rep: string representation
3173 // Invariants:
3174 // 1. String really contains _M_length + 1 characters: due to 21.3.4
3175 // must be kept null-terminated.
3176 // 2. _M_capacity >= _M_length
3177 // Allocated memory is always (_M_capacity + 1) * sizeof(_CharT).
3178 // 3. _M_refcount has three states:
3179 // -1: leaked, one reference, no ref-copies allowed, non-const.
3180 // 0: one reference, non-const.
3181 // n>0: n + 1 references, operations require a lock, const.
3182 // 4. All fields==0 is an empty string, given the extra storage
3183 // beyond-the-end for a null terminator; thus, the shared
3184 // empty string representation needs no constructor.
3185
3186 struct _Rep_base
3187 {
3188 size_type _M_length;
3189 size_type _M_capacity;
3190 _Atomic_word _M_refcount;
3191 };
3192
3193 struct _Rep : _Rep_base
3194 {
3195 // Types:
3196 typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
3197 rebind<char>::other _Raw_bytes_alloc;
3198
3199 // (Public) Data members:
3200
3201 // The maximum number of individual char_type elements of an
3202 // individual string is determined by _S_max_size. This is the
3203 // value that will be returned by max_size(). (Whereas npos
3204 // is the maximum number of bytes the allocator can allocate.)
3205 // If one was to divvy up the theoretical largest size string,
3206 // with a terminating character and m _CharT elements, it'd
3207 // look like this:
3208 // npos = sizeof(_Rep) + (m * sizeof(_CharT)) + sizeof(_CharT)
3209 // Solving for m:
3210 // m = ((npos - sizeof(_Rep))/sizeof(CharT)) - 1
3211 // In addition, this implementation quarters this amount.
3212 static const size_type _S_max_size;
3213 static const _CharT _S_terminal;
3214
3215 // The following storage is init'd to 0 by the linker, resulting
3216 // (carefully) in an empty string with one reference.
3217 static size_type _S_empty_rep_storage[];
3218
3219 static _Rep&
3220 _S_empty_rep() _GLIBCXX_NOEXCEPTnoexcept
3221 {
3222 // NB: Mild hack to avoid strict-aliasing warnings. Note that
3223 // _S_empty_rep_storage is never modified and the punning should
3224 // be reasonably safe in this case.
3225 void* __p = reinterpret_cast<void*>(&_S_empty_rep_storage);
3226 return *reinterpret_cast<_Rep*>(__p);
3227 }
3228
3229 bool
3230 _M_is_leaked() const _GLIBCXX_NOEXCEPTnoexcept
3231 {
3232#if defined(__GTHREADS1)
3233 // _M_refcount is mutated concurrently by _M_refcopy/_M_dispose,
3234 // so we need to use an atomic load. However, _M_is_leaked
3235 // predicate does not change concurrently (i.e. the string is either
3236 // leaked or not), so a relaxed load is enough.
3237 return __atomic_load_n(&this->_M_refcount, __ATOMIC_RELAXED0) < 0;
3238#else
3239 return this->_M_refcount < 0;
3240#endif
3241 }
3242
3243 bool
3244 _M_is_shared() const _GLIBCXX_NOEXCEPTnoexcept
3245 {
3246#if defined(__GTHREADS1)
3247 // _M_refcount is mutated concurrently by _M_refcopy/_M_dispose,
3248 // so we need to use an atomic load. Another thread can drop last
3249 // but one reference concurrently with this check, so we need this
3250 // load to be acquire to synchronize with release fetch_and_add in
3251 // _M_dispose.
3252 return __atomic_load_n(&this->_M_refcount, __ATOMIC_ACQUIRE2) > 0;
3253#else
3254 return this->_M_refcount > 0;
3255#endif
3256 }
3257
3258 void
3259 _M_set_leaked() _GLIBCXX_NOEXCEPTnoexcept
3260 { this->_M_refcount = -1; }
3261
3262 void
3263 _M_set_sharable() _GLIBCXX_NOEXCEPTnoexcept
3264 { this->_M_refcount = 0; }
3265
3266 void
3267 _M_set_length_and_sharable(size_type __n) _GLIBCXX_NOEXCEPTnoexcept
3268 {
3269#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
3270 if (__builtin_expect(this != &_S_empty_rep(), false))
3271#endif
3272 {
3273 this->_M_set_sharable(); // One reference.
3274 this->_M_length = __n;
3275 traits_type::assign(this->_M_refdata()[__n], _S_terminal);
3276 // grrr. (per 21.3.4)
3277 // You cannot leave those LWG people alone for a second.
3278 }
3279 }
3280
3281 _CharT*
3282 _M_refdata() throw()
3283 { return reinterpret_cast<_CharT*>(this + 1); }
3284
3285 _CharT*
3286 _M_grab(const _Alloc& __alloc1, const _Alloc& __alloc2)
3287 {
3288 return (!_M_is_leaked() && __alloc1 == __alloc2)
3289 ? _M_refcopy() : _M_clone(__alloc1);
3290 }
3291
3292 // Create & Destroy
3293 static _Rep*
3294 _S_create(size_type, size_type, const _Alloc&);
3295
3296 void
3297 _M_dispose(const _Alloc& __a) _GLIBCXX_NOEXCEPTnoexcept
3298 {
3299#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
3300 if (__builtin_expect(this != &_S_empty_rep(), false))
3301#endif
3302 {
3303 // Be race-detector-friendly. For more info see bits/c++config.
3304 _GLIBCXX_SYNCHRONIZATION_HAPPENS_BEFORE(&this->_M_refcount);
3305 // Decrement of _M_refcount is acq_rel, because:
3306 // - all but last decrements need to release to synchronize with
3307 // the last decrement that will delete the object.
3308 // - the last decrement needs to acquire to synchronize with
3309 // all the previous decrements.
3310 // - last but one decrement needs to release to synchronize with
3311 // the acquire load in _M_is_shared that will conclude that
3312 // the object is not shared anymore.
3313 if (__gnu_cxx::__exchange_and_add_dispatch(&this->_M_refcount,
3314 -1) <= 0)
3315 {
3316 _GLIBCXX_SYNCHRONIZATION_HAPPENS_AFTER(&this->_M_refcount);
3317 _M_destroy(__a);
3318 }
3319 }
3320 } // XXX MT
3321
3322 void
3323 _M_destroy(const _Alloc&) throw();
3324
3325 _CharT*
3326 _M_refcopy() throw()
3327 {
3328#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
3329 if (__builtin_expect(this != &_S_empty_rep(), false))
3330#endif
3331 __gnu_cxx::__atomic_add_dispatch(&this->_M_refcount, 1);
3332 return _M_refdata();
3333 } // XXX MT
3334
3335 _CharT*
3336 _M_clone(const _Alloc&, size_type __res = 0);
3337 };
3338
3339 // Use empty-base optimization: http://www.cantrip.org/emptyopt.html
3340 struct _Alloc_hider : _Alloc
3341 {
3342 _Alloc_hider(_CharT* __dat, const _Alloc& __a) _GLIBCXX_NOEXCEPTnoexcept
3343 : _Alloc(__a), _M_p(__dat) { }
3344
3345 _CharT* _M_p; // The actual data.
3346 };
3347
3348 public:
3349 // Data Members (public):
3350 // NB: This is an unsigned type, and thus represents the maximum
3351 // size that the allocator can hold.
3352 /// Value returned by various member functions when they fail.
3353 static const size_type npos = static_cast<size_type>(-1);
3354
3355 private:
3356 // Data Members (private):
3357 mutable _Alloc_hider _M_dataplus;
3358
3359 _CharT*
3360 _M_data() const _GLIBCXX_NOEXCEPTnoexcept
3361 { return _M_dataplus._M_p; }
3362
3363 _CharT*
3364 _M_data(_CharT* __p) _GLIBCXX_NOEXCEPTnoexcept
3365 { return (_M_dataplus._M_p = __p); }
3366
3367 _Rep*
3368 _M_rep() const _GLIBCXX_NOEXCEPTnoexcept
3369 { return &((reinterpret_cast<_Rep*> (_M_data()))[-1]); }
3370
3371 // For the internal use we have functions similar to `begin'/`end'
3372 // but they do not call _M_leak.
3373 iterator
3374 _M_ibegin() const _GLIBCXX_NOEXCEPTnoexcept
3375 { return iterator(_M_data()); }
3376
3377 iterator
3378 _M_iend() const _GLIBCXX_NOEXCEPTnoexcept
3379 { return iterator(_M_data() + this->size()); }
3380
3381 void
3382 _M_leak() // for use in begin() & non-const op[]
3383 {
3384 if (!_M_rep()->_M_is_leaked())
3385 _M_leak_hard();
3386 }
3387
3388 size_type
3389 _M_check(size_type __pos, const char* __s) const
3390 {
3391 if (__pos > this->size())
3392 __throw_out_of_range_fmt(__N("%s: __pos (which is %zu) > "("%s: __pos (which is %zu) > " "this->size() (which is %zu)"
)
3393 "this->size() (which is %zu)")("%s: __pos (which is %zu) > " "this->size() (which is %zu)"
),
3394 __s, __pos, this->size());
3395 return __pos;
3396 }
3397
3398 void
3399 _M_check_length(size_type __n1, size_type __n2, const char* __s) const
3400 {
3401 if (this->max_size() - (this->size() - __n1) < __n2)
3402 __throw_length_error(__N(__s)(__s));
3403 }
3404
3405 // NB: _M_limit doesn't check for a bad __pos value.
3406 size_type
3407 _M_limit(size_type __pos, size_type __off) const _GLIBCXX_NOEXCEPTnoexcept
3408 {
3409 const bool __testoff = __off < this->size() - __pos;
3410 return __testoff ? __off : this->size() - __pos;
3411 }
3412
3413 // True if _Rep and source do not overlap.
3414 bool
3415 _M_disjunct(const _CharT* __s) const _GLIBCXX_NOEXCEPTnoexcept
3416 {
3417 return (less<const _CharT*>()(__s, _M_data())
3418 || less<const _CharT*>()(_M_data() + this->size(), __s));
3419 }
3420
3421 // When __n = 1 way faster than the general multichar
3422 // traits_type::copy/move/assign.
3423 static void
3424 _M_copy(_CharT* __d, const _CharT* __s, size_type __n) _GLIBCXX_NOEXCEPTnoexcept
3425 {
3426 if (__n == 1)
3427 traits_type::assign(*__d, *__s);
3428 else
3429 traits_type::copy(__d, __s, __n);
3430 }
3431
3432 static void
3433 _M_move(_CharT* __d, const _CharT* __s, size_type __n) _GLIBCXX_NOEXCEPTnoexcept
3434 {
3435 if (__n == 1)
3436 traits_type::assign(*__d, *__s);
3437 else
3438 traits_type::move(__d, __s, __n);
3439 }
3440
3441 static void
3442 _M_assign(_CharT* __d, size_type __n, _CharT __c) _GLIBCXX_NOEXCEPTnoexcept
3443 {
3444 if (__n == 1)
3445 traits_type::assign(*__d, __c);
3446 else
3447 traits_type::assign(__d, __n, __c);
3448 }
3449
3450 // _S_copy_chars is a separate template to permit specialization
3451 // to optimize for the common case of pointers as iterators.
3452 template<class _Iterator>
3453 static void
3454 _S_copy_chars(_CharT* __p, _Iterator __k1, _Iterator __k2)
3455 {
3456 for (; __k1 != __k2; ++__k1, (void)++__p)
3457 traits_type::assign(*__p, *__k1); // These types are off.
3458 }
3459
3460 static void
3461 _S_copy_chars(_CharT* __p, iterator __k1, iterator __k2) _GLIBCXX_NOEXCEPTnoexcept
3462 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
3463
3464 static void
3465 _S_copy_chars(_CharT* __p, const_iterator __k1, const_iterator __k2)
3466 _GLIBCXX_NOEXCEPTnoexcept
3467 { _S_copy_chars(__p, __k1.base(), __k2.base()); }
3468
3469 static void
3470 _S_copy_chars(_CharT* __p, _CharT* __k1, _CharT* __k2) _GLIBCXX_NOEXCEPTnoexcept
3471 { _M_copy(__p, __k1, __k2 - __k1); }
3472
3473 static void
3474 _S_copy_chars(_CharT* __p, const _CharT* __k1, const _CharT* __k2)
3475 _GLIBCXX_NOEXCEPTnoexcept
3476 { _M_copy(__p, __k1, __k2 - __k1); }
3477
3478 static int
3479 _S_compare(size_type __n1, size_type __n2) _GLIBCXX_NOEXCEPTnoexcept
3480 {
3481 const difference_type __d = difference_type(__n1 - __n2);
3482
3483 if (__d > __gnu_cxx::__numeric_traits<int>::__max)
3484 return __gnu_cxx::__numeric_traits<int>::__max;
3485 else if (__d < __gnu_cxx::__numeric_traits<int>::__min)
3486 return __gnu_cxx::__numeric_traits<int>::__min;
3487 else
3488 return int(__d);
3489 }
3490
3491 void
3492 _M_mutate(size_type __pos, size_type __len1, size_type __len2);
3493
3494 void
3495 _M_leak_hard();
3496
3497 static _Rep&
3498 _S_empty_rep() _GLIBCXX_NOEXCEPTnoexcept
3499 { return _Rep::_S_empty_rep(); }
3500
3501#if __cplusplus201402L >= 201703L
3502 // A helper type for avoiding boiler-plate.
3503 typedef basic_string_view<_CharT, _Traits> __sv_type;
3504
3505 template<typename _Tp, typename _Res>
3506 using _If_sv = enable_if_t<
3507 __and_<is_convertible<const _Tp&, __sv_type>,
3508 __not_<is_convertible<const _Tp*, const basic_string*>>,
3509 __not_<is_convertible<const _Tp&, const _CharT*>>>::value,
3510 _Res>;
3511
3512 // Allows an implicit conversion to __sv_type.
3513 static __sv_type
3514 _S_to_string_view(__sv_type __svt) noexcept
3515 { return __svt; }
3516
3517 // Wraps a string_view by explicit conversion and thus
3518 // allows to add an internal constructor that does not
3519 // participate in overload resolution when a string_view
3520 // is provided.
3521 struct __sv_wrapper
3522 {
3523 explicit __sv_wrapper(__sv_type __sv) noexcept : _M_sv(__sv) { }
3524 __sv_type _M_sv;
3525 };
3526
3527 /**
3528 * @brief Only internally used: Construct string from a string view
3529 * wrapper.
3530 * @param __svw string view wrapper.
3531 * @param __a Allocator to use.
3532 */
3533 explicit
3534 basic_string(__sv_wrapper __svw, const _Alloc& __a)
3535 : basic_string(__svw._M_sv.data(), __svw._M_sv.size(), __a) { }
3536#endif
3537
3538 public:
3539 // Construct/copy/destroy:
3540 // NB: We overload ctors in some cases instead of using default
3541 // arguments, per 17.4.4.4 para. 2 item 2.
3542
3543 /**
3544 * @brief Default constructor creates an empty string.
3545 */
3546 basic_string()
3547#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
3548 _GLIBCXX_NOEXCEPTnoexcept
3549 : _M_dataplus(_S_empty_rep()._M_refdata(), _Alloc())
3550#else
3551 : _M_dataplus(_S_construct(size_type(), _CharT(), _Alloc()), _Alloc())
3552#endif
3553 { }
3554
3555 /**
3556 * @brief Construct an empty string using allocator @a a.
3557 */
3558 explicit
3559 basic_string(const _Alloc& __a);
3560
3561 // NB: per LWG issue 42, semantics different from IS:
3562 /**
3563 * @brief Construct string with copy of value of @a str.
3564 * @param __str Source string.
3565 */
3566 basic_string(const basic_string& __str);
3567
3568 // _GLIBCXX_RESOLVE_LIB_DEFECTS
3569 // 2583. no way to supply an allocator for basic_string(str, pos)
3570 /**
3571 * @brief Construct string as copy of a substring.
3572 * @param __str Source string.
3573 * @param __pos Index of first character to copy from.
3574 * @param __a Allocator to use.
3575 */
3576 basic_string(const basic_string& __str, size_type __pos,
3577 const _Alloc& __a = _Alloc());
3578
3579 /**
3580 * @brief Construct string as copy of a substring.
3581 * @param __str Source string.
3582 * @param __pos Index of first character to copy from.
3583 * @param __n Number of characters to copy.
3584 */
3585 basic_string(const basic_string& __str, size_type __pos,
3586 size_type __n);
3587 /**
3588 * @brief Construct string as copy of a substring.
3589 * @param __str Source string.
3590 * @param __pos Index of first character to copy from.
3591 * @param __n Number of characters to copy.
3592 * @param __a Allocator to use.
3593 */
3594 basic_string(const basic_string& __str, size_type __pos,
3595 size_type __n, const _Alloc& __a);
3596
3597 /**
3598 * @brief Construct string initialized by a character %array.
3599 * @param __s Source character %array.
3600 * @param __n Number of characters to copy.
3601 * @param __a Allocator to use (default is default allocator).
3602 *
3603 * NB: @a __s must have at least @a __n characters, &apos;\\0&apos;
3604 * has no special meaning.
3605 */
3606 basic_string(const _CharT* __s, size_type __n,
3607 const _Alloc& __a = _Alloc());
3608
3609 /**
3610 * @brief Construct string as copy of a C string.
3611 * @param __s Source C string.
3612 * @param __a Allocator to use (default is default allocator).
3613 */
3614#if __cpp_deduction_guides && ! defined _GLIBCXX_DEFINING_STRING_INSTANTIATIONS
3615 // _GLIBCXX_RESOLVE_LIB_DEFECTS
3616 // 3076. basic_string CTAD ambiguity
3617 template<typename = _RequireAllocator<_Alloc>>
3618#endif
3619 basic_string(const _CharT* __s, const _Alloc& __a = _Alloc())
3620 : _M_dataplus(_S_construct(__s, __s ? __s + traits_type::length(__s) :
3621 __s + npos, __a), __a)
3622 { }
3623
3624 /**
3625 * @brief Construct string as multiple characters.
3626 * @param __n Number of characters.
3627 * @param __c Character to use.
3628 * @param __a Allocator to use (default is default allocator).
3629 */
3630 basic_string(size_type __n, _CharT __c, const _Alloc& __a = _Alloc());
3631
3632#if __cplusplus201402L >= 201103L
3633 /**
3634 * @brief Move construct string.
3635 * @param __str Source string.
3636 *
3637 * The newly-created string contains the exact contents of @a __str.
3638 * @a __str is a valid, but unspecified string.
3639 **/
3640 basic_string(basic_string&& __str)
3641#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
3642 noexcept // FIXME C++11: should always be noexcept.
3643#endif
3644 : _M_dataplus(std::move(__str._M_dataplus))
3645 {
3646#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
3647 __str._M_data(_S_empty_rep()._M_refdata());
3648#else
3649 __str._M_data(_S_construct(size_type(), _CharT(), get_allocator()));
3650#endif
3651 }
3652
3653 /**
3654 * @brief Construct string from an initializer %list.
3655 * @param __l std::initializer_list of characters.
3656 * @param __a Allocator to use (default is default allocator).
3657 */
3658 basic_string(initializer_list<_CharT> __l, const _Alloc& __a = _Alloc());
3659
3660 basic_string(const basic_string& __str, const _Alloc& __a)
3661 : _M_dataplus(__str._M_rep()->_M_grab(__a, __str.get_allocator()), __a)
3662 { }
3663
3664 basic_string(basic_string&& __str, const _Alloc& __a)
3665 : _M_dataplus(__str._M_data(), __a)
3666 {
3667 if (__a == __str.get_allocator())
3668 {
3669#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
3670 __str._M_data(_S_empty_rep()._M_refdata());
3671#else
3672 __str._M_data(_S_construct(size_type(), _CharT(), __a));
3673#endif
3674 }
3675 else
3676 _M_dataplus._M_p = _S_construct(__str.begin(), __str.end(), __a);
3677 }
3678#endif // C++11
3679
3680 /**
3681 * @brief Construct string as copy of a range.
3682 * @param __beg Start of range.
3683 * @param __end End of range.
3684 * @param __a Allocator to use (default is default allocator).
3685 */
3686 template<class _InputIterator>
3687 basic_string(_InputIterator __beg, _InputIterator __end,
3688 const _Alloc& __a = _Alloc());
3689
3690#if __cplusplus201402L >= 201703L
3691 /**
3692 * @brief Construct string from a substring of a string_view.
3693 * @param __t Source object convertible to string view.
3694 * @param __pos The index of the first character to copy from __t.
3695 * @param __n The number of characters to copy from __t.
3696 * @param __a Allocator to use.
3697 */
3698 template<typename _Tp, typename = _If_sv<_Tp, void>>
3699 basic_string(const _Tp& __t, size_type __pos, size_type __n,
3700 const _Alloc& __a = _Alloc())
3701 : basic_string(_S_to_string_view(__t).substr(__pos, __n), __a) { }
3702
3703 /**
3704 * @brief Construct string from a string_view.
3705 * @param __t Source object convertible to string view.
3706 * @param __a Allocator to use (default is default allocator).
3707 */
3708 template<typename _Tp, typename = _If_sv<_Tp, void>>
3709 explicit
3710 basic_string(const _Tp& __t, const _Alloc& __a = _Alloc())
3711 : basic_string(__sv_wrapper(_S_to_string_view(__t)), __a) { }
3712#endif // C++17
3713
3714 /**
3715 * @brief Destroy the string instance.
3716 */
3717 ~basic_string() _GLIBCXX_NOEXCEPTnoexcept
3718 { _M_rep()->_M_dispose(this->get_allocator()); }
3719
3720 /**
3721 * @brief Assign the value of @a str to this string.
3722 * @param __str Source string.
3723 */
3724 basic_string&
3725 operator=(const basic_string& __str)
3726 { return this->assign(__str); }
3727
3728 /**
3729 * @brief Copy contents of @a s into this string.
3730 * @param __s Source null-terminated string.
3731 */
3732 basic_string&
3733 operator=(const _CharT* __s)
3734 { return this->assign(__s); }
3735
3736 /**
3737 * @brief Set value to string of length 1.
3738 * @param __c Source character.
3739 *
3740 * Assigning to a character makes this string length 1 and
3741 * (*this)[0] == @a c.
3742 */
3743 basic_string&
3744 operator=(_CharT __c)
3745 {
3746 this->assign(1, __c);
3747 return *this;
3748 }
3749
3750#if __cplusplus201402L >= 201103L
3751 /**
3752 * @brief Move assign the value of @a str to this string.
3753 * @param __str Source string.
3754 *
3755 * The contents of @a str are moved into this string (without copying).
3756 * @a str is a valid, but unspecified string.
3757 **/
3758 basic_string&
3759 operator=(basic_string&& __str)
3760 _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value)noexcept(allocator_traits<_Alloc>::is_always_equal::value
)
3761 {
3762 // NB: DR 1204.
3763 this->swap(__str);
3764 return *this;
3765 }
3766
3767 /**
3768 * @brief Set value to string constructed from initializer %list.
3769 * @param __l std::initializer_list.
3770 */
3771 basic_string&
3772 operator=(initializer_list<_CharT> __l)
3773 {
3774 this->assign(__l.begin(), __l.size());
3775 return *this;
3776 }
3777#endif // C++11
3778
3779#if __cplusplus201402L >= 201703L
3780 /**
3781 * @brief Set value to string constructed from a string_view.
3782 * @param __svt An object convertible to string_view.
3783 */
3784 template<typename _Tp>
3785 _If_sv<_Tp, basic_string&>
3786 operator=(const _Tp& __svt)
3787 { return this->assign(__svt); }
3788
3789 /**
3790 * @brief Convert to a string_view.
3791 * @return A string_view.
3792 */
3793 operator __sv_type() const noexcept
3794 { return __sv_type(data(), size()); }
3795#endif // C++17
3796
3797 // Iterators:
3798 /**
3799 * Returns a read/write iterator that points to the first character in
3800 * the %string. Unshares the string.
3801 */
3802 iterator
3803 begin() // FIXME C++11: should be noexcept.
3804 {
3805 _M_leak();
3806 return iterator(_M_data());
3807 }
3808
3809 /**
3810 * Returns a read-only (constant) iterator that points to the first
3811 * character in the %string.
3812 */
3813 const_iterator
3814 begin() const _GLIBCXX_NOEXCEPTnoexcept
3815 { return const_iterator(_M_data()); }
3816
3817 /**
3818 * Returns a read/write iterator that points one past the last
3819 * character in the %string. Unshares the string.
3820 */
3821 iterator
3822 end() // FIXME C++11: should be noexcept.
3823 {
3824 _M_leak();
3825 return iterator(_M_data() + this->size());
3826 }
3827
3828 /**
3829 * Returns a read-only (constant) iterator that points one past the
3830 * last character in the %string.
3831 */
3832 const_iterator
3833 end() const _GLIBCXX_NOEXCEPTnoexcept
3834 { return const_iterator(_M_data() + this->size()); }
3835
3836 /**
3837 * Returns a read/write reverse iterator that points to the last
3838 * character in the %string. Iteration is done in reverse element
3839 * order. Unshares the string.
3840 */
3841 reverse_iterator
3842 rbegin() // FIXME C++11: should be noexcept.
3843 { return reverse_iterator(this->end()); }
3844
3845 /**
3846 * Returns a read-only (constant) reverse iterator that points
3847 * to the last character in the %string. Iteration is done in
3848 * reverse element order.
3849 */
3850 const_reverse_iterator
3851 rbegin() const _GLIBCXX_NOEXCEPTnoexcept
3852 { return const_reverse_iterator(this->end()); }
3853
3854 /**
3855 * Returns a read/write reverse iterator that points to one before the
3856 * first character in the %string. Iteration is done in reverse
3857 * element order. Unshares the string.
3858 */
3859 reverse_iterator
3860 rend() // FIXME C++11: should be noexcept.
3861 { return reverse_iterator(this->begin()); }
3862
3863 /**
3864 * Returns a read-only (constant) reverse iterator that points
3865 * to one before the first character in the %string. Iteration
3866 * is done in reverse element order.
3867 */
3868 const_reverse_iterator
3869 rend() const _GLIBCXX_NOEXCEPTnoexcept
3870 { return const_reverse_iterator(this->begin()); }
3871
3872#if __cplusplus201402L >= 201103L
3873 /**
3874 * Returns a read-only (constant) iterator that points to the first
3875 * character in the %string.
3876 */
3877 const_iterator
3878 cbegin() const noexcept
3879 { return const_iterator(this->_M_data()); }
3880
3881 /**
3882 * Returns a read-only (constant) iterator that points one past the
3883 * last character in the %string.
3884 */
3885 const_iterator
3886 cend() const noexcept
3887 { return const_iterator(this->_M_data() + this->size()); }
3888
3889 /**
3890 * Returns a read-only (constant) reverse iterator that points
3891 * to the last character in the %string. Iteration is done in
3892 * reverse element order.
3893 */
3894 const_reverse_iterator
3895 crbegin() const noexcept
3896 { return const_reverse_iterator(this->end()); }
3897
3898 /**
3899 * Returns a read-only (constant) reverse iterator that points
3900 * to one before the first character in the %string. Iteration
3901 * is done in reverse element order.
3902 */
3903 const_reverse_iterator
3904 crend() const noexcept
3905 { return const_reverse_iterator(this->begin()); }
3906#endif
3907
3908 public:
3909 // Capacity:
3910 /// Returns the number of characters in the string, not including any
3911 /// null-termination.
3912 size_type
3913 size() const _GLIBCXX_NOEXCEPTnoexcept
3914 { return _M_rep()->_M_length; }
3915
3916 /// Returns the number of characters in the string, not including any
3917 /// null-termination.
3918 size_type
3919 length() const _GLIBCXX_NOEXCEPTnoexcept
3920 { return _M_rep()->_M_length; }
3921
3922 /// Returns the size() of the largest possible %string.
3923 size_type
3924 max_size() const _GLIBCXX_NOEXCEPTnoexcept
3925 { return _Rep::_S_max_size; }
3926
3927 /**
3928 * @brief Resizes the %string to the specified number of characters.
3929 * @param __n Number of characters the %string should contain.
3930 * @param __c Character to fill any new elements.
3931 *
3932 * This function will %resize the %string to the specified
3933 * number of characters. If the number is smaller than the
3934 * %string's current size the %string is truncated, otherwise
3935 * the %string is extended and new elements are %set to @a __c.
3936 */
3937 void
3938 resize(size_type __n, _CharT __c);
3939
3940 /**
3941 * @brief Resizes the %string to the specified number of characters.
3942 * @param __n Number of characters the %string should contain.
3943 *
3944 * This function will resize the %string to the specified length. If
3945 * the new size is smaller than the %string's current size the %string
3946 * is truncated, otherwise the %string is extended and new characters
3947 * are default-constructed. For basic types such as char, this means
3948 * setting them to 0.
3949 */
3950 void
3951 resize(size_type __n)
3952 { this->resize(__n, _CharT()); }
3953
3954#if __cplusplus201402L >= 201103L
3955 /// A non-binding request to reduce capacity() to size().
3956 void
3957 shrink_to_fit() _GLIBCXX_NOEXCEPTnoexcept
3958 {
3959#if __cpp_exceptions
3960 if (capacity() > size())
3961 {
3962 try
3963 { reserve(0); }
3964 catch(...)
3965 { }
3966 }
3967#endif
3968 }
3969#endif
3970
3971 /**
3972 * Returns the total number of characters that the %string can hold
3973 * before needing to allocate more memory.
3974 */
3975 size_type
3976 capacity() const _GLIBCXX_NOEXCEPTnoexcept
3977 { return _M_rep()->_M_capacity; }
3978
3979 /**
3980 * @brief Attempt to preallocate enough memory for specified number of
3981 * characters.
3982 * @param __res_arg Number of characters required.
3983 * @throw std::length_error If @a __res_arg exceeds @c max_size().
3984 *
3985 * This function attempts to reserve enough memory for the
3986 * %string to hold the specified number of characters. If the
3987 * number requested is more than max_size(), length_error is
3988 * thrown.
3989 *
3990 * The advantage of this function is that if optimal code is a
3991 * necessity and the user can determine the string length that will be
3992 * required, the user can reserve the memory in %advance, and thus
3993 * prevent a possible reallocation of memory and copying of %string
3994 * data.
3995 */
3996 void
3997 reserve(size_type __res_arg = 0);
3998
3999 /**
4000 * Erases the string, making it empty.
4001 */
4002#if _GLIBCXX_FULLY_DYNAMIC_STRING0 == 0
4003 void
4004 clear() _GLIBCXX_NOEXCEPTnoexcept
4005 {
4006 if (_M_rep()->_M_is_shared())
4007 {
4008 _M_rep()->_M_dispose(this->get_allocator());
4009 _M_data(_S_empty_rep()._M_refdata());
4010 }
4011 else
4012 _M_rep()->_M_set_length_and_sharable(0);
4013 }
4014#else
4015 // PR 56166: this should not throw.
4016 void
4017 clear()
4018 { _M_mutate(0, this->size(), 0); }
4019#endif
4020
4021 /**
4022 * Returns true if the %string is empty. Equivalent to
4023 * <code>*this == ""</code>.
4024 */
4025 _GLIBCXX_NODISCARD bool
4026 empty() const _GLIBCXX_NOEXCEPTnoexcept
4027 { return this->size() == 0; }
4028
4029 // Element access:
4030 /**
4031 * @brief Subscript access to the data contained in the %string.
4032 * @param __pos The index of the character to access.
4033 * @return Read-only (constant) reference to the character.
4034 *
4035 * This operator allows for easy, array-style, data access.
4036 * Note that data access with this operator is unchecked and
4037 * out_of_range lookups are not defined. (For checked lookups
4038 * see at().)
4039 */
4040 const_reference
4041 operator[] (size_type __pos) const _GLIBCXX_NOEXCEPTnoexcept
4042 {
4043 __glibcxx_assert(__pos <= size());
4044 return _M_data()[__pos];
4045 }
4046
4047 /**
4048 * @brief Subscript access to the data contained in the %string.
4049 * @param __pos The index of the character to access.
4050 * @return Read/write reference to the character.
4051 *
4052 * This operator allows for easy, array-style, data access.
4053 * Note that data access with this operator is unchecked and
4054 * out_of_range lookups are not defined. (For checked lookups
4055 * see at().) Unshares the string.
4056 */
4057 reference
4058 operator[](size_type __pos)
4059 {
4060 // Allow pos == size() both in C++98 mode, as v3 extension,
4061 // and in C++11 mode.
4062 __glibcxx_assert(__pos <= size());
4063 // In pedantic mode be strict in C++98 mode.
4064 _GLIBCXX_DEBUG_PEDASSERT(__cplusplus >= 201103L || __pos < size());
4065 _M_leak();
4066 return _M_data()[__pos];
4067 }
4068
4069 /**
4070 * @brief Provides access to the data contained in the %string.
4071 * @param __n The index of the character to access.
4072 * @return Read-only (const) reference to the character.
4073 * @throw std::out_of_range If @a n is an invalid index.
4074 *
4075 * This function provides for safer data access. The parameter is
4076 * first checked that it is in the range of the string. The function
4077 * throws out_of_range if the check fails.
4078 */
4079 const_reference
4080 at(size_type __n) const
4081 {
4082 if (__n >= this->size())
4083 __throw_out_of_range_fmt(__N("basic_string::at: __n "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
4084 "(which is %zu) >= this->size() "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
4085 "(which is %zu)")("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)"),
4086 __n, this->size());
4087 return _M_data()[__n];
4088 }
4089
4090 /**
4091 * @brief Provides access to the data contained in the %string.
4092 * @param __n The index of the character to access.
4093 * @return Read/write reference to the character.
4094 * @throw std::out_of_range If @a n is an invalid index.
4095 *
4096 * This function provides for safer data access. The parameter is
4097 * first checked that it is in the range of the string. The function
4098 * throws out_of_range if the check fails. Success results in
4099 * unsharing the string.
4100 */
4101 reference
4102 at(size_type __n)
4103 {
4104 if (__n >= size())
4105 __throw_out_of_range_fmt(__N("basic_string::at: __n "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
4106 "(which is %zu) >= this->size() "("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)")
4107 "(which is %zu)")("basic_string::at: __n " "(which is %zu) >= this->size() "
"(which is %zu)"),
4108 __n, this->size());
4109 _M_leak();
4110 return _M_data()[__n];
4111 }
4112
4113#if __cplusplus201402L >= 201103L
4114 /**
4115 * Returns a read/write reference to the data at the first
4116 * element of the %string.
4117 */
4118 reference
4119 front()
4120 {
4121 __glibcxx_assert(!empty());
4122 return operator[](0);
4123 }
4124
4125 /**
4126 * Returns a read-only (constant) reference to the data at the first
4127 * element of the %string.
4128 */
4129 const_reference
4130 front() const noexcept
4131 {
4132 __glibcxx_assert(!empty());
4133 return operator[](0);
4134 }
4135
4136 /**
4137 * Returns a read/write reference to the data at the last
4138 * element of the %string.
4139 */
4140 reference
4141 back()
4142 {
4143 __glibcxx_assert(!empty());
4144 return operator[](this->size() - 1);
4145 }
4146
4147 /**
4148 * Returns a read-only (constant) reference to the data at the
4149 * last element of the %string.
4150 */
4151 const_reference
4152 back() const noexcept
4153 {
4154 __glibcxx_assert(!empty());
4155 return operator[](this->size() - 1);
4156 }
4157#endif
4158
4159 // Modifiers:
4160 /**
4161 * @brief Append a string to this string.
4162 * @param __str The string to append.
4163 * @return Reference to this string.
4164 */
4165 basic_string&
4166 operator+=(const basic_string& __str)
4167 { return this->append(__str); }
4168
4169 /**
4170 * @brief Append a C string.
4171 * @param __s The C string to append.
4172 * @return Reference to this string.
4173 */
4174 basic_string&
4175 operator+=(const _CharT* __s)
4176 { return this->append(__s); }
4177
4178 /**
4179 * @brief Append a character.
4180 * @param __c The character to append.
4181 * @return Reference to this string.
4182 */
4183 basic_string&
4184 operator+=(_CharT __c)
4185 {
4186 this->push_back(__c);
4187 return *this;
4188 }
4189
4190#if __cplusplus201402L >= 201103L
4191 /**
4192 * @brief Append an initializer_list of characters.
4193 * @param __l The initializer_list of characters to be appended.
4194 * @return Reference to this string.
4195 */
4196 basic_string&
4197 operator+=(initializer_list<_CharT> __l)
4198 { return this->append(__l.begin(), __l.size()); }
4199#endif // C++11
4200
4201#if __cplusplus201402L >= 201703L
4202 /**
4203 * @brief Append a string_view.
4204 * @param __svt The object convertible to string_view to be appended.
4205 * @return Reference to this string.
4206 */
4207 template<typename _Tp>
4208 _If_sv<_Tp, basic_string&>
4209 operator+=(const _Tp& __svt)
4210 { return this->append(__svt); }
4211#endif // C++17
4212
4213 /**
4214 * @brief Append a string to this string.
4215 * @param __str The string to append.
4216 * @return Reference to this string.
4217 */
4218 basic_string&
4219 append(const basic_string& __str);
4220
4221 /**
4222 * @brief Append a substring.
4223 * @param __str The string to append.
4224 * @param __pos Index of the first character of str to append.
4225 * @param __n The number of characters to append.
4226 * @return Reference to this string.
4227 * @throw std::out_of_range if @a __pos is not a valid index.
4228 *
4229 * This function appends @a __n characters from @a __str
4230 * starting at @a __pos to this string. If @a __n is is larger
4231 * than the number of available characters in @a __str, the
4232 * remainder of @a __str is appended.
4233 */
4234 basic_string&
4235 append(const basic_string& __str, size_type __pos, size_type __n = npos);
4236
4237 /**
4238 * @brief Append a C substring.
4239 * @param __s The C string to append.
4240 * @param __n The number of characters to append.
4241 * @return Reference to this string.
4242 */
4243 basic_string&
4244 append(const _CharT* __s, size_type __n);
4245
4246 /**
4247 * @brief Append a C string.
4248 * @param __s The C string to append.
4249 * @return Reference to this string.
4250 */
4251 basic_string&
4252 append(const _CharT* __s)
4253 {
4254 __glibcxx_requires_string(__s);
4255 return this->append(__s, traits_type::length(__s));
4256 }
4257
4258 /**
4259 * @brief Append multiple characters.
4260 * @param __n The number of characters to append.
4261 * @param __c The character to use.
4262 * @return Reference to this string.
4263 *
4264 * Appends __n copies of __c to this string.
4265 */
4266 basic_string&
4267 append(size_type __n, _CharT __c);
4268
4269#if __cplusplus201402L >= 201103L
4270 /**
4271 * @brief Append an initializer_list of characters.
4272 * @param __l The initializer_list of characters to append.
4273 * @return Reference to this string.
4274 */
4275 basic_string&
4276 append(initializer_list<_CharT> __l)
4277 { return this->append(__l.begin(), __l.size()); }
4278#endif // C++11
4279
4280 /**
4281 * @brief Append a range of characters.
4282 * @param __first Iterator referencing the first character to append.
4283 * @param __last Iterator marking the end of the range.
4284 * @return Reference to this string.
4285 *
4286 * Appends characters in the range [__first,__last) to this string.
4287 */
4288 template<class _InputIterator>
4289 basic_string&
4290 append(_InputIterator __first, _InputIterator __last)
4291 { return this->replace(_M_iend(), _M_iend(), __first, __last); }
4292
4293#if __cplusplus201402L >= 201703L
4294 /**
4295 * @brief Append a string_view.
4296 * @param __svt The object convertible to string_view to be appended.
4297 * @return Reference to this string.
4298 */
4299 template<typename _Tp>
4300 _If_sv<_Tp, basic_string&>
4301 append(const _Tp& __svt)
4302 {
4303 __sv_type __sv = __svt;
4304 return this->append(__sv.data(), __sv.size());
4305 }
4306
4307 /**
4308 * @brief Append a range of characters from a string_view.
4309 * @param __svt The object convertible to string_view to be appended
4310 * from.
4311 * @param __pos The position in the string_view to append from.
4312 * @param __n The number of characters to append from the string_view.
4313 * @return Reference to this string.
4314 */
4315 template<typename _Tp>
4316 _If_sv<_Tp, basic_string&>
4317 append(const _Tp& __svt, size_type __pos, size_type __n = npos)
4318 {
4319 __sv_type __sv = __svt;
4320 return append(__sv.data()
4321 + std::__sv_check(__sv.size(), __pos, "basic_string::append"),
4322 std::__sv_limit(__sv.size(), __pos, __n));
4323 }
4324#endif // C++17
4325
4326 /**
4327 * @brief Append a single character.
4328 * @param __c Character to append.
4329 */
4330 void
4331 push_back(_CharT __c)
4332 {
4333 const size_type __len = 1 + this->size();
4334 if (__len > this->capacity() || _M_rep()->_M_is_shared())
4335 this->reserve(__len);
4336 traits_type::assign(_M_data()[this->size()], __c);
4337 _M_rep()->_M_set_length_and_sharable(__len);
4338 }
4339
4340 /**
4341 * @brief Set value to contents of another string.
4342 * @param __str Source string to use.
4343 * @return Reference to this string.
4344 */
4345 basic_string&
4346 assign(const basic_string& __str);
4347
4348#if __cplusplus201402L >= 201103L
4349 /**
4350 * @brief Set value to contents of another string.
4351 * @param __str Source string to use.
4352 * @return Reference to this string.
4353 *
4354 * This function sets this string to the exact contents of @a __str.
4355 * @a __str is a valid, but unspecified string.
4356 */
4357 basic_string&
4358 assign(basic_string&& __str)
4359 noexcept(allocator_traits<_Alloc>::is_always_equal::value)
4360 {
4361 this->swap(__str);
4362 return *this;
4363 }
4364#endif // C++11
4365
4366 /**
4367 * @brief Set value to a substring of a string.
4368 * @param __str The string to use.
4369 * @param __pos Index of the first character of str.
4370 * @param __n Number of characters to use.
4371 * @return Reference to this string.
4372 * @throw std::out_of_range if @a pos is not a valid index.
4373 *
4374 * This function sets this string to the substring of @a __str
4375 * consisting of @a __n characters at @a __pos. If @a __n is
4376 * is larger than the number of available characters in @a
4377 * __str, the remainder of @a __str is used.
4378 */
4379 basic_string&
4380 assign(const basic_string& __str, size_type __pos, size_type __n = npos)
4381 { return this->assign(__str._M_data()
4382 + __str._M_check(__pos, "basic_string::assign"),
4383 __str._M_limit(__pos, __n)); }
4384
4385 /**
4386 * @brief Set value to a C substring.
4387 * @param __s The C string to use.
4388 * @param __n Number of characters to use.
4389 * @return Reference to this string.
4390 *
4391 * This function sets the value of this string to the first @a __n
4392 * characters of @a __s. If @a __n is is larger than the number of
4393 * available characters in @a __s, the remainder of @a __s is used.
4394 */
4395 basic_string&
4396 assign(const _CharT* __s, size_type __n);
4397
4398 /**
4399 * @brief Set value to contents of a C string.
4400 * @param __s The C string to use.
4401 * @return Reference to this string.
4402 *
4403 * This function sets the value of this string to the value of @a __s.
4404 * The data is copied, so there is no dependence on @a __s once the
4405 * function returns.
4406 */
4407 basic_string&
4408 assign(const _CharT* __s)
4409 {
4410 __glibcxx_requires_string(__s);
4411 return this->assign(__s, traits_type::length(__s));
4412 }
4413
4414 /**
4415 * @brief Set value to multiple characters.
4416 * @param __n Length of the resulting string.
4417 * @param __c The character to use.
4418 * @return Reference to this string.
4419 *
4420 * This function sets the value of this string to @a __n copies of
4421 * character @a __c.
4422 */
4423 basic_string&
4424 assign(size_type __n, _CharT __c)
4425 { return _M_replace_aux(size_type(0), this->size(), __n, __c); }
4426
4427 /**
4428 * @brief Set value to a range of characters.
4429 * @param __first Iterator referencing the first character to append.
4430 * @param __last Iterator marking the end of the range.
4431 * @return Reference to this string.
4432 *
4433 * Sets value of string to characters in the range [__first,__last).
4434 */
4435 template<class _InputIterator>
4436 basic_string&
4437 assign(_InputIterator __first, _InputIterator __last)
4438 { return this->replace(_M_ibegin(), _M_iend(), __first, __last); }
4439
4440#if __cplusplus201402L >= 201103L
4441 /**
4442 * @brief Set value to an initializer_list of characters.
4443 * @param __l The initializer_list of characters to assign.
4444 * @return Reference to this string.
4445 */
4446 basic_string&
4447 assign(initializer_list<_CharT> __l)
4448 { return this->assign(__l.begin(), __l.size()); }
4449#endif // C++11
4450
4451#if __cplusplus201402L >= 201703L
4452 /**
4453 * @brief Set value from a string_view.
4454 * @param __svt The source object convertible to string_view.
4455 * @return Reference to this string.
4456 */
4457 template<typename _Tp>
4458 _If_sv<_Tp, basic_string&>
4459 assign(const _Tp& __svt)
4460 {
4461 __sv_type __sv = __svt;
4462 return this->assign(__sv.data(), __sv.size());
4463 }
4464
4465 /**
4466 * @brief Set value from a range of characters in a string_view.
4467 * @param __svt The source object convertible to string_view.
4468 * @param __pos The position in the string_view to assign from.
4469 * @param __n The number of characters to assign.
4470 * @return Reference to this string.
4471 */
4472 template<typename _Tp>
4473 _If_sv<_Tp, basic_string&>
4474 assign(const _Tp& __svt, size_type __pos, size_type __n = npos)
4475 {
4476 __sv_type __sv = __svt;
4477 return assign(__sv.data()
4478 + std::__sv_check(__sv.size(), __pos, "basic_string::assign"),
4479 std::__sv_limit(__sv.size(), __pos, __n));
4480 }
4481#endif // C++17
4482
4483 /**
4484 * @brief Insert multiple characters.
4485 * @param __p Iterator referencing location in string to insert at.
4486 * @param __n Number of characters to insert
4487 * @param __c The character to insert.
4488 * @throw std::length_error If new length exceeds @c max_size().
4489 *
4490 * Inserts @a __n copies of character @a __c starting at the
4491 * position referenced by iterator @a __p. If adding
4492 * characters causes the length to exceed max_size(),
4493 * length_error is thrown. The value of the string doesn't
4494 * change if an error is thrown.
4495 */
4496 void
4497 insert(iterator __p, size_type __n, _CharT __c)
4498 { this->replace(__p, __p, __n, __c); }
4499
4500 /**
4501 * @brief Insert a range of characters.
4502 * @param __p Iterator referencing location in string to insert at.
4503 * @param __beg Start of range.
4504 * @param __end End of range.
4505 * @throw std::length_error If new length exceeds @c max_size().
4506 *
4507 * Inserts characters in range [__beg,__end). If adding
4508 * characters causes the length to exceed max_size(),
4509 * length_error is thrown. The value of the string doesn't
4510 * change if an error is thrown.
4511 */
4512 template<class _InputIterator>
4513 void
4514 insert(iterator __p, _InputIterator __beg, _InputIterator __end)
4515 { this->replace(__p, __p, __beg, __end); }
4516
4517#if __cplusplus201402L >= 201103L
4518 /**
4519 * @brief Insert an initializer_list of characters.
4520 * @param __p Iterator referencing location in string to insert at.
4521 * @param __l The initializer_list of characters to insert.
4522 * @throw std::length_error If new length exceeds @c max_size().
4523 */
4524 void
4525 insert(iterator __p, initializer_list<_CharT> __l)
4526 {
4527 _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
4528 this->insert(__p - _M_ibegin(), __l.begin(), __l.size());
4529 }
4530#endif // C++11
4531
4532 /**
4533 * @brief Insert value of a string.
4534 * @param __pos1 Position in string to insert at.
4535 * @param __str The string to insert.
4536 * @return Reference to this string.
4537 * @throw std::length_error If new length exceeds @c max_size().
4538 *
4539 * Inserts value of @a __str starting at @a __pos1. If adding
4540 * characters causes the length to exceed max_size(),
4541 * length_error is thrown. The value of the string doesn't
4542 * change if an error is thrown.
4543 */
4544 basic_string&
4545 insert(size_type __pos1, const basic_string& __str)
4546 { return this->insert(__pos1, __str, size_type(0), __str.size()); }
4547
4548 /**
4549 * @brief Insert a substring.
4550 * @param __pos1 Position in string to insert at.
4551 * @param __str The string to insert.
4552 * @param __pos2 Start of characters in str to insert.
4553 * @param __n Number of characters to insert.
4554 * @return Reference to this string.
4555 * @throw std::length_error If new length exceeds @c max_size().
4556 * @throw std::out_of_range If @a pos1 > size() or
4557 * @a __pos2 > @a str.size().
4558 *
4559 * Starting at @a pos1, insert @a __n character of @a __str
4560 * beginning with @a __pos2. If adding characters causes the
4561 * length to exceed max_size(), length_error is thrown. If @a
4562 * __pos1 is beyond the end of this string or @a __pos2 is
4563 * beyond the end of @a __str, out_of_range is thrown. The
4564 * value of the string doesn't change if an error is thrown.
4565 */
4566 basic_string&
4567 insert(size_type __pos1, const basic_string& __str,
4568 size_type __pos2, size_type __n = npos)
4569 { return this->insert(__pos1, __str._M_data()
4570 + __str._M_check(__pos2, "basic_string::insert"),
4571 __str._M_limit(__pos2, __n)); }
4572
4573 /**
4574 * @brief Insert a C substring.
4575 * @param __pos Position in string to insert at.
4576 * @param __s The C string to insert.
4577 * @param __n The number of characters to insert.
4578 * @return Reference to this string.
4579 * @throw std::length_error If new length exceeds @c max_size().
4580 * @throw std::out_of_range If @a __pos is beyond the end of this
4581 * string.
4582 *
4583 * Inserts the first @a __n characters of @a __s starting at @a
4584 * __pos. If adding characters causes the length to exceed
4585 * max_size(), length_error is thrown. If @a __pos is beyond
4586 * end(), out_of_range is thrown. The value of the string
4587 * doesn't change if an error is thrown.
4588 */
4589 basic_string&
4590 insert(size_type __pos, const _CharT* __s, size_type __n);
4591
4592 /**
4593 * @brief Insert a C string.
4594 * @param __pos Position in string to insert at.
4595 * @param __s The C string to insert.
4596 * @return Reference to this string.
4597 * @throw std::length_error If new length exceeds @c max_size().
4598 * @throw std::out_of_range If @a pos is beyond the end of this
4599 * string.
4600 *
4601 * Inserts the first @a n characters of @a __s starting at @a __pos. If
4602 * adding characters causes the length to exceed max_size(),
4603 * length_error is thrown. If @a __pos is beyond end(), out_of_range is
4604 * thrown. The value of the string doesn't change if an error is
4605 * thrown.
4606 */
4607 basic_string&
4608 insert(size_type __pos, const _CharT* __s)
4609 {
4610 __glibcxx_requires_string(__s);
4611 return this->insert(__pos, __s, traits_type::length(__s));
4612 }
4613
4614 /**
4615 * @brief Insert multiple characters.
4616 * @param __pos Index in string to insert at.
4617 * @param __n Number of characters to insert
4618 * @param __c The character to insert.
4619 * @return Reference to this string.
4620 * @throw std::length_error If new length exceeds @c max_size().
4621 * @throw std::out_of_range If @a __pos is beyond the end of this
4622 * string.
4623 *
4624 * Inserts @a __n copies of character @a __c starting at index
4625 * @a __pos. If adding characters causes the length to exceed
4626 * max_size(), length_error is thrown. If @a __pos > length(),
4627 * out_of_range is thrown. The value of the string doesn't
4628 * change if an error is thrown.
4629 */
4630 basic_string&
4631 insert(size_type __pos, size_type __n, _CharT __c)
4632 { return _M_replace_aux(_M_check(__pos, "basic_string::insert"),
4633 size_type(0), __n, __c); }
4634
4635 /**
4636 * @brief Insert one character.
4637 * @param __p Iterator referencing position in string to insert at.
4638 * @param __c The character to insert.
4639 * @return Iterator referencing newly inserted char.
4640 * @throw std::length_error If new length exceeds @c max_size().
4641 *
4642 * Inserts character @a __c at position referenced by @a __p.
4643 * If adding character causes the length to exceed max_size(),
4644 * length_error is thrown. If @a __p is beyond end of string,
4645 * out_of_range is thrown. The value of the string doesn't
4646 * change if an error is thrown.
4647 */
4648 iterator
4649 insert(iterator __p, _CharT __c)
4650 {
4651 _GLIBCXX_DEBUG_PEDASSERT(__p >= _M_ibegin() && __p <= _M_iend());
4652 const size_type __pos = __p - _M_ibegin();
4653 _M_replace_aux(__pos, size_type(0), size_type(1), __c);
4654 _M_rep()->_M_set_leaked();
4655 return iterator(_M_data() + __pos);
4656 }
4657
4658#if __cplusplus201402L >= 201703L
4659 /**
4660 * @brief Insert a string_view.
4661 * @param __pos Position in string to insert at.
4662 * @param __svt The object convertible to string_view to insert.
4663 * @return Reference to this string.
4664 */
4665 template<typename _Tp>
4666 _If_sv<_Tp, basic_string&>
4667 insert(size_type __pos, const _Tp& __svt)
4668 {
4669 __sv_type __sv = __svt;
4670 return this->insert(__pos, __sv.data(), __sv.size());
4671 }
4672
4673 /**
4674 * @brief Insert a string_view.
4675 * @param __pos Position in string to insert at.
4676 * @param __svt The object convertible to string_view to insert from.
4677 * @param __pos Position in string_view to insert
4678 * from.
4679 * @param __n The number of characters to insert.
4680 * @return Reference to this string.
4681 */
4682 template<typename _Tp>
4683 _If_sv<_Tp, basic_string&>
4684 insert(size_type __pos1, const _Tp& __svt,
4685 size_type __pos2, size_type __n = npos)
4686 {
4687 __sv_type __sv = __svt;
4688 return this->replace(__pos1, size_type(0), __sv.data()
4689 + std::__sv_check(__sv.size(), __pos2, "basic_string::insert"),
4690 std::__sv_limit(__sv.size(), __pos2, __n));
4691 }
4692#endif // C++17
4693
4694 /**
4695 * @brief Remove characters.
4696 * @param __pos Index of first character to remove (default 0).
4697 * @param __n Number of characters to remove (default remainder).
4698 * @return Reference to this string.
4699 * @throw std::out_of_range If @a pos is beyond the end of this
4700 * string.
4701 *
4702 * Removes @a __n characters from this string starting at @a
4703 * __pos. The length of the string is reduced by @a __n. If
4704 * there are < @a __n characters to remove, the remainder of
4705 * the string is truncated. If @a __p is beyond end of string,
4706 * out_of_range is thrown. The value of the string doesn't
4707 * change if an error is thrown.
4708 */
4709 basic_string&
4710 erase(size_type __pos = 0, size_type __n = npos)
4711 {
4712 _M_mutate(_M_check(__pos, "basic_string::erase"),
4713 _M_limit(__pos, __n), size_type(0));
4714 return *this;
4715 }
4716
4717 /**
4718 * @brief Remove one character.
4719 * @param __position Iterator referencing the character to remove.
4720 * @return iterator referencing same location after removal.
4721 *
4722 * Removes the character at @a __position from this string. The value
4723 * of the string doesn't change if an error is thrown.
4724 */
4725 iterator
4726 erase(iterator __position)
4727 {
4728 _GLIBCXX_DEBUG_PEDASSERT(__position >= _M_ibegin()
4729 && __position < _M_iend());
4730 const size_type __pos = __position - _M_ibegin();
4731 _M_mutate(__pos, size_type(1), size_type(0));
4732 _M_rep()->_M_set_leaked();
4733 return iterator(_M_data() + __pos);
4734 }
4735
4736 /**
4737 * @brief Remove a range of characters.
4738 * @param __first Iterator referencing the first character to remove.
4739 * @param __last Iterator referencing the end of the range.
4740 * @return Iterator referencing location of first after removal.
4741 *
4742 * Removes the characters in the range [first,last) from this string.
4743 * The value of the string doesn't change if an error is thrown.
4744 */
4745 iterator
4746 erase(iterator __first, iterator __last);
4747
4748#if __cplusplus201402L >= 201103L
4749 /**
4750 * @brief Remove the last character.
4751 *
4752 * The string must be non-empty.
4753 */
4754 void
4755 pop_back() // FIXME C++11: should be noexcept.
4756 {
4757 __glibcxx_assert(!empty());
4758 erase(size() - 1, 1);
4759 }
4760#endif // C++11
4761
4762 /**
4763 * @brief Replace characters with value from another string.
4764 * @param __pos Index of first character to replace.
4765 * @param __n Number of characters to be replaced.
4766 * @param __str String to insert.
4767 * @return Reference to this string.
4768 * @throw std::out_of_range If @a pos is beyond the end of this
4769 * string.
4770 * @throw std::length_error If new length exceeds @c max_size().
4771 *
4772 * Removes the characters in the range [__pos,__pos+__n) from
4773 * this string. In place, the value of @a __str is inserted.
4774 * If @a __pos is beyond end of string, out_of_range is thrown.
4775 * If the length of the result exceeds max_size(), length_error
4776 * is thrown. The value of the string doesn't change if an
4777 * error is thrown.
4778 */
4779 basic_string&
4780 replace(size_type __pos, size_type __n, const basic_string& __str)
4781 { return this->replace(__pos, __n, __str._M_data(), __str.size()); }
4782
4783 /**
4784 * @brief Replace characters with value from another string.
4785 * @param __pos1 Index of first character to replace.
4786 * @param __n1 Number of characters to be replaced.
4787 * @param __str String to insert.
4788 * @param __pos2 Index of first character of str to use.
4789 * @param __n2 Number of characters from str to use.
4790 * @return Reference to this string.
4791 * @throw std::out_of_range If @a __pos1 > size() or @a __pos2 >
4792 * __str.size().
4793 * @throw std::length_error If new length exceeds @c max_size().
4794 *
4795 * Removes the characters in the range [__pos1,__pos1 + n) from this
4796 * string. In place, the value of @a __str is inserted. If @a __pos is
4797 * beyond end of string, out_of_range is thrown. If the length of the
4798 * result exceeds max_size(), length_error is thrown. The value of the
4799 * string doesn't change if an error is thrown.
4800 */
4801 basic_string&
4802 replace(size_type __pos1, size_type __n1, const basic_string& __str,
4803 size_type __pos2, size_type __n2 = npos)
4804 { return this->replace(__pos1, __n1, __str._M_data()
4805 + __str._M_check(__pos2, "basic_string::replace"),
4806 __str._M_limit(__pos2, __n2)); }
4807
4808 /**
4809 * @brief Replace characters with value of a C substring.
4810 * @param __pos Index of first character to replace.
4811 * @param __n1 Number of characters to be replaced.
4812 * @param __s C string to insert.
4813 * @param __n2 Number of characters from @a s to use.
4814 * @return Reference to this string.
4815 * @throw std::out_of_range If @a pos1 > size().
4816 * @throw std::length_error If new length exceeds @c max_size().
4817 *
4818 * Removes the characters in the range [__pos,__pos + __n1)
4819 * from this string. In place, the first @a __n2 characters of
4820 * @a __s are inserted, or all of @a __s if @a __n2 is too large. If
4821 * @a __pos is beyond end of string, out_of_range is thrown. If
4822 * the length of result exceeds max_size(), length_error is
4823 * thrown. The value of the string doesn't change if an error
4824 * is thrown.
4825 */
4826 basic_string&
4827 replace(size_type __pos, size_type __n1, const _CharT* __s,
4828 size_type __n2);
4829
4830 /**
4831 * @brief Replace characters with value of a C string.
4832 * @param __pos Index of first character to replace.
4833 * @param __n1 Number of characters to be replaced.
4834 * @param __s C string to insert.
4835 * @return Reference to this string.
4836 * @throw std::out_of_range If @a pos > size().
4837 * @throw std::length_error If new length exceeds @c max_size().
4838 *
4839 * Removes the characters in the range [__pos,__pos + __n1)
4840 * from this string. In place, the characters of @a __s are
4841 * inserted. If @a __pos is beyond end of string, out_of_range
4842 * is thrown. If the length of result exceeds max_size(),
4843 * length_error is thrown. The value of the string doesn't
4844 * change if an error is thrown.
4845 */
4846 basic_string&
4847 replace(size_type __pos, size_type __n1, const _CharT* __s)
4848 {
4849 __glibcxx_requires_string(__s);
4850 return this->replace(__pos, __n1, __s, traits_type::length(__s));
4851 }
4852
4853 /**
4854 * @brief Replace characters with multiple characters.
4855 * @param __pos Index of first character to replace.
4856 * @param __n1 Number of characters to be replaced.
4857 * @param __n2 Number of characters to insert.
4858 * @param __c Character to insert.
4859 * @return Reference to this string.
4860 * @throw std::out_of_range If @a __pos > size().
4861 * @throw std::length_error If new length exceeds @c max_size().
4862 *
4863 * Removes the characters in the range [pos,pos + n1) from this
4864 * string. In place, @a __n2 copies of @a __c are inserted.
4865 * If @a __pos is beyond end of string, out_of_range is thrown.
4866 * If the length of result exceeds max_size(), length_error is
4867 * thrown. The value of the string doesn't change if an error
4868 * is thrown.
4869 */
4870 basic_string&
4871 replace(size_type __pos, size_type __n1, size_type __n2, _CharT __c)
4872 { return _M_replace_aux(_M_check(__pos, "basic_string::replace"),
4873 _M_limit(__pos, __n1), __n2, __c); }
4874
4875 /**
4876 * @brief Replace range of characters with string.
4877 * @param __i1 Iterator referencing start of range to replace.
4878 * @param __i2 Iterator referencing end of range to replace.
4879 * @param __str String value to insert.
4880 * @return Reference to this string.
4881 * @throw std::length_error If new length exceeds @c max_size().
4882 *
4883 * Removes the characters in the range [__i1,__i2). In place,
4884 * the value of @a __str is inserted. If the length of result
4885 * exceeds max_size(), length_error is thrown. The value of
4886 * the string doesn't change if an error is thrown.
4887 */
4888 basic_string&
4889 replace(iterator __i1, iterator __i2, const basic_string& __str)
4890 { return this->replace(__i1, __i2, __str._M_data(), __str.size()); }
4891
4892 /**
4893 * @brief Replace range of characters with C substring.
4894 * @param __i1 Iterator referencing start of range to replace.
4895 * @param __i2 Iterator referencing end of range to replace.
4896 * @param __s C string value to insert.
4897 * @param __n Number of characters from s to insert.
4898 * @return Reference to this string.
4899 * @throw std::length_error If new length exceeds @c max_size().
4900 *
4901 * Removes the characters in the range [__i1,__i2). In place,
4902 * the first @a __n characters of @a __s are inserted. If the
4903 * length of result exceeds max_size(), length_error is thrown.
4904 * The value of the string doesn't change if an error is
4905 * thrown.
4906 */
4907 basic_string&
4908 replace(iterator __i1, iterator __i2, const _CharT* __s, size_type __n)
4909 {
4910 _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
4911 && __i2 <= _M_iend());
4912 return this->replace(__i1 - _M_ibegin(), __i2 - __i1, __s, __n);
4913 }
4914
4915 /**
4916 * @brief Replace range of characters with C string.
4917 * @param __i1 Iterator referencing start of range to replace.
4918 * @param __i2 Iterator referencing end of range to replace.
4919 * @param __s C string value to insert.
4920 * @return Reference to this string.
4921 * @throw std::length_error If new length exceeds @c max_size().
4922 *
4923 * Removes the characters in the range [__i1,__i2). In place,
4924 * the characters of @a __s are inserted. If the length of
4925 * result exceeds max_size(), length_error is thrown. The
4926 * value of the string doesn't change if an error is thrown.
4927 */
4928 basic_string&
4929 replace(iterator __i1, iterator __i2, const _CharT* __s)
4930 {
4931 __glibcxx_requires_string(__s);
4932 return this->replace(__i1, __i2, __s, traits_type::length(__s));
4933 }
4934
4935 /**
4936 * @brief Replace range of characters with multiple characters
4937 * @param __i1 Iterator referencing start of range to replace.
4938 * @param __i2 Iterator referencing end of range to replace.
4939 * @param __n Number of characters to insert.
4940 * @param __c Character to insert.
4941 * @return Reference to this string.
4942 * @throw std::length_error If new length exceeds @c max_size().
4943 *
4944 * Removes the characters in the range [__i1,__i2). In place,
4945 * @a __n copies of @a __c are inserted. If the length of
4946 * result exceeds max_size(), length_error is thrown. The
4947 * value of the string doesn't change if an error is thrown.
4948 */
4949 basic_string&
4950 replace(iterator __i1, iterator __i2, size_type __n, _CharT __c)
4951 {
4952 _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
4953 && __i2 <= _M_iend());
4954 return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __c);
4955 }
4956
4957 /**
4958 * @brief Replace range of characters with range.
4959 * @param __i1 Iterator referencing start of range to replace.
4960 * @param __i2 Iterator referencing end of range to replace.
4961 * @param __k1 Iterator referencing start of range to insert.
4962 * @param __k2 Iterator referencing end of range to insert.
4963 * @return Reference to this string.
4964 * @throw std::length_error If new length exceeds @c max_size().
4965 *
4966 * Removes the characters in the range [__i1,__i2). In place,
4967 * characters in the range [__k1,__k2) are inserted. If the
4968 * length of result exceeds max_size(), length_error is thrown.
4969 * The value of the string doesn't change if an error is
4970 * thrown.
4971 */
4972 template<class _InputIterator>
4973 basic_string&
4974 replace(iterator __i1, iterator __i2,
4975 _InputIterator __k1, _InputIterator __k2)
4976 {
4977 _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
4978 && __i2 <= _M_iend());
4979 __glibcxx_requires_valid_range(__k1, __k2);
4980 typedef typename std::__is_integer<_InputIterator>::__type _Integral;
4981 return _M_replace_dispatch(__i1, __i2, __k1, __k2, _Integral());
4982 }
4983
4984 // Specializations for the common case of pointer and iterator:
4985 // useful to avoid the overhead of temporary buffering in _M_replace.
4986 basic_string&
4987 replace(iterator __i1, iterator __i2, _CharT* __k1, _CharT* __k2)
4988 {
4989 _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
4990 && __i2 <= _M_iend());
4991 __glibcxx_requires_valid_range(__k1, __k2);
4992 return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
4993 __k1, __k2 - __k1);
4994 }
4995
4996 basic_string&
4997 replace(iterator __i1, iterator __i2,
4998 const _CharT* __k1, const _CharT* __k2)
4999 {
5000 _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
5001 && __i2 <= _M_iend());
5002 __glibcxx_requires_valid_range(__k1, __k2);
5003 return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
5004 __k1, __k2 - __k1);
5005 }
5006
5007 basic_string&
5008 replace(iterator __i1, iterator __i2, iterator __k1, iterator __k2)
5009 {
5010 _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
5011 && __i2 <= _M_iend());
5012 __glibcxx_requires_valid_range(__k1, __k2);
5013 return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
5014 __k1.base(), __k2 - __k1);
5015 }
5016
5017 basic_string&
5018 replace(iterator __i1, iterator __i2,
5019 const_iterator __k1, const_iterator __k2)
5020 {
5021 _GLIBCXX_DEBUG_PEDASSERT(_M_ibegin() <= __i1 && __i1 <= __i2
5022 && __i2 <= _M_iend());
5023 __glibcxx_requires_valid_range(__k1, __k2);
5024 return this->replace(__i1 - _M_ibegin(), __i2 - __i1,
5025 __k1.base(), __k2 - __k1);
5026 }
5027
5028#if __cplusplus201402L >= 201103L
5029 /**
5030 * @brief Replace range of characters with initializer_list.
5031 * @param __i1 Iterator referencing start of range to replace.
5032 * @param __i2 Iterator referencing end of range to replace.
5033 * @param __l The initializer_list of characters to insert.
5034 * @return Reference to this string.
5035 * @throw std::length_error If new length exceeds @c max_size().
5036 *
5037 * Removes the characters in the range [__i1,__i2). In place,
5038 * characters in the range [__k1,__k2) are inserted. If the
5039 * length of result exceeds max_size(), length_error is thrown.
5040 * The value of the string doesn't change if an error is
5041 * thrown.
5042 */
5043 basic_string& replace(iterator __i1, iterator __i2,
5044 initializer_list<_CharT> __l)
5045 { return this->replace(__i1, __i2, __l.begin(), __l.end()); }
5046#endif // C++11
5047
5048#if __cplusplus201402L >= 201703L
5049 /**
5050 * @brief Replace range of characters with string_view.
5051 * @param __pos The position to replace at.
5052 * @param __n The number of characters to replace.
5053 * @param __svt The object convertible to string_view to insert.
5054 * @return Reference to this string.
5055 */
5056 template<typename _Tp>
5057 _If_sv<_Tp, basic_string&>
5058 replace(size_type __pos, size_type __n, const _Tp& __svt)
5059 {
5060 __sv_type __sv = __svt;
5061 return this->replace(__pos, __n, __sv.data(), __sv.size());
5062 }
5063
5064 /**
5065 * @brief Replace range of characters with string_view.
5066 * @param __pos1 The position to replace at.
5067 * @param __n1 The number of characters to replace.
5068 * @param __svt The object convertible to string_view to insert from.
5069 * @param __pos2 The position in the string_view to insert from.
5070 * @param __n2 The number of characters to insert.
5071 * @return Reference to this string.
5072 */
5073 template<typename _Tp>
5074 _If_sv<_Tp, basic_string&>
5075 replace(size_type __pos1, size_type __n1, const _Tp& __svt,
5076 size_type __pos2, size_type __n2 = npos)
5077 {
5078 __sv_type __sv = __svt;
5079 return this->replace(__pos1, __n1,
5080 __sv.data()
5081 + std::__sv_check(__sv.size(), __pos2, "basic_string::replace"),
5082 std::__sv_limit(__sv.size(), __pos2, __n2));
5083 }
5084
5085 /**
5086 * @brief Replace range of characters with string_view.
5087 * @param __i1 An iterator referencing the start position
5088 to replace at.
5089 * @param __i2 An iterator referencing the end position
5090 for the replace.
5091 * @param __svt The object convertible to string_view to insert from.
5092 * @return Reference to this string.
5093 */
5094 template<typename _Tp>
5095 _If_sv<_Tp, basic_string&>
5096 replace(const_iterator __i1, const_iterator __i2, const _Tp& __svt)
5097 {
5098 __sv_type __sv = __svt;
5099 return this->replace(__i1 - begin(), __i2 - __i1, __sv);
5100 }
5101#endif // C++17
5102
5103 private:
5104 template<class _Integer>
5105 basic_string&
5106 _M_replace_dispatch(iterator __i1, iterator __i2, _Integer __n,
5107 _Integer __val, __true_type)
5108 { return _M_replace_aux(__i1 - _M_ibegin(), __i2 - __i1, __n, __val); }
5109
5110 template<class _InputIterator>
5111 basic_string&
5112 _M_replace_dispatch(iterator __i1, iterator __i2, _InputIterator __k1,
5113 _InputIterator __k2, __false_type);
5114
5115 basic_string&
5116 _M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
5117 _CharT __c);
5118
5119 basic_string&
5120 _M_replace_safe(size_type __pos1, size_type __n1, const _CharT* __s,
5121 size_type __n2);
5122
5123 // _S_construct_aux is used to implement the 21.3.1 para 15 which
5124 // requires special behaviour if _InIter is an integral type
5125 template<class _InIterator>
5126 static _CharT*
5127 _S_construct_aux(_InIterator __beg, _InIterator __end,
5128 const _Alloc& __a, __false_type)
5129 {
5130 typedef typename iterator_traits<_InIterator>::iterator_category _Tag;
5131 return _S_construct(__beg, __end, __a, _Tag());
5132 }
5133
5134 // _GLIBCXX_RESOLVE_LIB_DEFECTS
5135 // 438. Ambiguity in the "do the right thing" clause
5136 template<class _Integer>
5137 static _CharT*
5138 _S_construct_aux(_Integer __beg, _Integer __end,
5139 const _Alloc& __a, __true_type)
5140 { return _S_construct_aux_2(static_cast<size_type>(__beg),
5141 __end, __a); }
5142
5143 static _CharT*
5144 _S_construct_aux_2(size_type __req, _CharT __c, const _Alloc& __a)
5145 { return _S_construct(__req, __c, __a); }
5146
5147 template<class _InIterator>
5148 static _CharT*
5149 _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a)
5150 {
5151 typedef typename std::__is_integer<_InIterator>::__type _Integral;
5152 return _S_construct_aux(__beg, __end, __a, _Integral());
5153 }
5154
5155 // For Input Iterators, used in istreambuf_iterators, etc.
5156 template<class _InIterator>
5157 static _CharT*
5158 _S_construct(_InIterator __beg, _InIterator __end, const _Alloc& __a,
5159 input_iterator_tag);
5160
5161 // For forward_iterators up to random_access_iterators, used for
5162 // string::iterator, _CharT*, etc.
5163 template<class _FwdIterator>
5164 static _CharT*
5165 _S_construct(_FwdIterator __beg, _FwdIterator __end, const _Alloc& __a,
5166 forward_iterator_tag);
5167
5168 static _CharT*
5169 _S_construct(size_type __req, _CharT __c, const _Alloc& __a);
5170
5171 public:
5172
5173 /**
5174 * @brief Copy substring into C string.
5175 * @param __s C string to copy value into.
5176 * @param __n Number of characters to copy.
5177 * @param __pos Index of first character to copy.
5178 * @return Number of characters actually copied
5179 * @throw std::out_of_range If __pos > size().
5180 *
5181 * Copies up to @a __n characters starting at @a __pos into the
5182 * C string @a __s. If @a __pos is %greater than size(),
5183 * out_of_range is thrown.
5184 */
5185 size_type
5186 copy(_CharT* __s, size_type __n, size_type __pos = 0) const;
5187
5188 /**
5189 * @brief Swap contents with another string.
5190 * @param __s String to swap with.
5191 *
5192 * Exchanges the contents of this string with that of @a __s in constant
5193 * time.
5194 */
5195 void
5196 swap(basic_string& __s)
5197 _GLIBCXX_NOEXCEPT_IF(allocator_traits<_Alloc>::is_always_equal::value)noexcept(allocator_traits<_Alloc>::is_always_equal::value
);
5198
5199 // String operations:
5200 /**
5201 * @brief Return const pointer to null-terminated contents.
5202 *
5203 * This is a handle to internal data. Do not modify or dire things may
5204 * happen.
5205 */
5206 const _CharT*
5207 c_str() const _GLIBCXX_NOEXCEPTnoexcept
5208 { return _M_data(); }
5209
5210 /**
5211 * @brief Return const pointer to contents.
5212 *
5213 * This is a pointer to internal data. It is undefined to modify
5214 * the contents through the returned pointer. To get a pointer that
5215 * allows modifying the contents use @c &str[0] instead,
5216 * (or in C++17 the non-const @c str.data() overload).
5217 */
5218 const _CharT*
5219 data() const _GLIBCXX_NOEXCEPTnoexcept
5220 { return _M_data(); }
5221
5222#if __cplusplus201402L >= 201703L
5223 /**
5224 * @brief Return non-const pointer to contents.
5225 *
5226 * This is a pointer to the character sequence held by the string.
5227 * Modifying the characters in the sequence is allowed.
5228 */
5229 _CharT*
5230 data() noexcept
5231 {
5232 _M_leak();
5233 return _M_data();
5234 }
5235#endif
5236
5237 /**
5238 * @brief Return copy of allocator used to construct this string.
5239 */
5240 allocator_type
5241 get_allocator() const _GLIBCXX_NOEXCEPTnoexcept
5242 { return _M_dataplus; }
5243
5244 /**
5245 * @brief Find position of a C substring.
5246 * @param __s C string to locate.
5247 * @param __pos Index of character to search from.
5248 * @param __n Number of characters from @a s to search for.
5249 * @return Index of start of first occurrence.
5250 *
5251 * Starting from @a __pos, searches forward for the first @a
5252 * __n characters in @a __s within this string. If found,
5253 * returns the index where it begins. If not found, returns
5254 * npos.
5255 */
5256 size_type
5257 find(const _CharT* __s, size_type __pos, size_type __n) const
5258 _GLIBCXX_NOEXCEPTnoexcept;
5259
5260 /**
5261 * @brief Find position of a string.
5262 * @param __str String to locate.
5263 * @param __pos Index of character to search from (default 0).
5264 * @return Index of start of first occurrence.
5265 *
5266 * Starting from @a __pos, searches forward for value of @a __str within
5267 * this string. If found, returns the index where it begins. If not
5268 * found, returns npos.
5269 */
5270 size_type
5271 find(const basic_string& __str, size_type __pos = 0) const
5272 _GLIBCXX_NOEXCEPTnoexcept
5273 { return this->find(__str.data(), __pos, __str.size()); }
5274
5275 /**
5276 * @brief Find position of a C string.
5277 * @param __s C string to locate.
5278 * @param __pos Index of character to search from (default 0).
5279 * @return Index of start of first occurrence.
5280 *
5281 * Starting from @a __pos, searches forward for the value of @a
5282 * __s within this string. If found, returns the index where
5283 * it begins. If not found, returns npos.
5284 */
5285 size_type
5286 find(const _CharT* __s, size_type __pos = 0) const _GLIBCXX_NOEXCEPTnoexcept
5287 {
5288 __glibcxx_requires_string(__s);
5289 return this->find(__s, __pos, traits_type::length(__s));
5290 }
5291
5292 /**
5293 * @brief Find position of a character.
5294 * @param __c Character to locate.
5295 * @param __pos Index of character to search from (default 0).
5296 * @return Index of first occurrence.
5297 *
5298 * Starting from @a __pos, searches forward for @a __c within
5299 * this string. If found, returns the index where it was
5300 * found. If not found, returns npos.
5301 */
5302 size_type
5303 find(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPTnoexcept;
5304
5305#if __cplusplus201402L >= 201703L
5306 /**
5307 * @brief Find position of a string_view.
5308 * @param __svt The object convertible to string_view to locate.
5309 * @param __pos Index of character to search from (default 0).
5310 * @return Index of start of first occurrence.
5311 */
5312 template<typename _Tp>
5313 _If_sv<_Tp, size_type>
5314 find(const _Tp& __svt, size_type __pos = 0) const
5315 noexcept(is_same<_Tp, __sv_type>::value)
5316 {
5317 __sv_type __sv = __svt;
5318 return this->find(__sv.data(), __pos, __sv.size());
5319 }
5320#endif // C++17
5321
5322 /**
5323 * @brief Find last position of a string.
5324 * @param __str String to locate.
5325 * @param __pos Index of character to search back from (default end).
5326 * @return Index of start of last occurrence.
5327 *
5328 * Starting from @a __pos, searches backward for value of @a
5329 * __str within this string. If found, returns the index where
5330 * it begins. If not found, returns npos.
5331 */
5332 size_type
5333 rfind(const basic_string& __str, size_type __pos = npos) const
5334 _GLIBCXX_NOEXCEPTnoexcept
5335 { return this->rfind(__str.data(), __pos, __str.size()); }
5336
5337 /**
5338 * @brief Find last position of a C substring.
5339 * @param __s C string to locate.
5340 * @param __pos Index of character to search back from.
5341 * @param __n Number of characters from s to search for.
5342 * @return Index of start of last occurrence.
5343 *
5344 * Starting from @a __pos, searches backward for the first @a
5345 * __n characters in @a __s within this string. If found,
5346 * returns the index where it begins. If not found, returns
5347 * npos.
5348 */
5349 size_type
5350 rfind(const _CharT* __s, size_type __pos, size_type __n) const
5351 _GLIBCXX_NOEXCEPTnoexcept;
5352
5353 /**
5354 * @brief Find last position of a C string.
5355 * @param __s C string to locate.
5356 * @param __pos Index of character to start search at (default end).
5357 * @return Index of start of last occurrence.
5358 *
5359 * Starting from @a __pos, searches backward for the value of
5360 * @a __s within this string. If found, returns the index
5361 * where it begins. If not found, returns npos.
5362 */
5363 size_type
5364 rfind(const _CharT* __s, size_type __pos = npos) const _GLIBCXX_NOEXCEPTnoexcept
5365 {
5366 __glibcxx_requires_string(__s);
5367 return this->rfind(__s, __pos, traits_type::length(__s));
5368 }
5369
5370 /**
5371 * @brief Find last position of a character.
5372 * @param __c Character to locate.
5373 * @param __pos Index of character to search back from (default end).
5374 * @return Index of last occurrence.
5375 *
5376 * Starting from @a __pos, searches backward for @a __c within
5377 * this string. If found, returns the index where it was
5378 * found. If not found, returns npos.
5379 */
5380 size_type
5381 rfind(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPTnoexcept;
5382
5383#if __cplusplus201402L >= 201703L
5384 /**
5385 * @brief Find last position of a string_view.
5386 * @param __svt The object convertible to string_view to locate.
5387 * @param __pos Index of character to search back from (default end).
5388 * @return Index of start of last occurrence.
5389 */
5390 template<typename _Tp>
5391 _If_sv<_Tp, size_type>
5392 rfind(const _Tp& __svt, size_type __pos = npos) const
5393 noexcept(is_same<_Tp, __sv_type>::value)
5394 {
5395 __sv_type __sv = __svt;
5396 return this->rfind(__sv.data(), __pos, __sv.size());
5397 }
5398#endif // C++17
5399
5400 /**
5401 * @brief Find position of a character of string.
5402 * @param __str String containing characters to locate.
5403 * @param __pos Index of character to search from (default 0).
5404 * @return Index of first occurrence.
5405 *
5406 * Starting from @a __pos, searches forward for one of the
5407 * characters of @a __str within this string. If found,
5408 * returns the index where it was found. If not found, returns
5409 * npos.
5410 */
5411 size_type
5412 find_first_of(const basic_string& __str, size_type __pos = 0) const
5413 _GLIBCXX_NOEXCEPTnoexcept
5414 { return this->find_first_of(__str.data(), __pos, __str.size()); }
5415
5416 /**
5417 * @brief Find position of a character of C substring.
5418 * @param __s String containing characters to locate.
5419 * @param __pos Index of character to search from.
5420 * @param __n Number of characters from s to search for.
5421 * @return Index of first occurrence.
5422 *
5423 * Starting from @a __pos, searches forward for one of the
5424 * first @a __n characters of @a __s within this string. If
5425 * found, returns the index where it was found. If not found,
5426 * returns npos.
5427 */
5428 size_type
5429 find_first_of(const _CharT* __s, size_type __pos, size_type __n) const
5430 _GLIBCXX_NOEXCEPTnoexcept;
5431
5432 /**
5433 * @brief Find position of a character of C string.
5434 * @param __s String containing characters to locate.
5435 * @param __pos Index of character to search from (default 0).
5436 * @return Index of first occurrence.
5437 *
5438 * Starting from @a __pos, searches forward for one of the
5439 * characters of @a __s within this string. If found, returns
5440 * the index where it was found. If not found, returns npos.
5441 */
5442 size_type
5443 find_first_of(const _CharT* __s, size_type __pos = 0) const
5444 _GLIBCXX_NOEXCEPTnoexcept
5445 {
5446 __glibcxx_requires_string(__s);
5447 return this->find_first_of(__s, __pos, traits_type::length(__s));
5448 }
5449
5450 /**
5451 * @brief Find position of a character.
5452 * @param __c Character to locate.
5453 * @param __pos Index of character to search from (default 0).
5454 * @return Index of first occurrence.
5455 *
5456 * Starting from @a __pos, searches forward for the character
5457 * @a __c within this string. If found, returns the index
5458 * where it was found. If not found, returns npos.
5459 *
5460 * Note: equivalent to find(__c, __pos).
5461 */
5462 size_type
5463 find_first_of(_CharT __c, size_type __pos = 0) const _GLIBCXX_NOEXCEPTnoexcept
5464 { return this->find(__c, __pos); }
5465
5466#if __cplusplus201402L >= 201703L
5467 /**
5468 * @brief Find position of a character of a string_view.
5469 * @param __svt An object convertible to string_view containing
5470 * characters to locate.
5471 * @param __pos Index of character to search from (default 0).
5472 * @return Index of first occurrence.
5473 */
5474 template<typename _Tp>
5475 _If_sv<_Tp, size_type>
5476 find_first_of(const _Tp& __svt, size_type __pos = 0) const
5477 noexcept(is_same<_Tp, __sv_type>::value)
5478 {
5479 __sv_type __sv = __svt;
5480 return this->find_first_of(__sv.data(), __pos, __sv.size());
5481 }
5482#endif // C++17
5483
5484 /**
5485 * @brief Find last position of a character of string.
5486 * @param __str String containing characters to locate.
5487 * @param __pos Index of character to search back from (default end).
5488 * @return Index of last occurrence.
5489 *
5490 * Starting from @a __pos, searches backward for one of the
5491 * characters of @a __str within this string. If found,
5492 * returns the index where it was found. If not found, returns
5493 * npos.
5494 */
5495 size_type
5496 find_last_of(const basic_string& __str, size_type __pos = npos) const
5497 _GLIBCXX_NOEXCEPTnoexcept
5498 { return this->find_last_of(__str.data(), __pos, __str.size()); }
5499
5500 /**
5501 * @brief Find last position of a character of C substring.
5502 * @param __s C string containing characters to locate.
5503 * @param __pos Index of character to search back from.
5504 * @param __n Number of characters from s to search for.
5505 * @return Index of last occurrence.
5506 *
5507 * Starting from @a __pos, searches backward for one of the
5508 * first @a __n characters of @a __s within this string. If
5509 * found, returns the index where it was found. If not found,
5510 * returns npos.
5511 */
5512 size_type
5513 find_last_of(const _CharT* __s, size_type __pos, size_type __n) const
5514 _GLIBCXX_NOEXCEPTnoexcept;
5515
5516 /**
5517 * @brief Find last position of a character of C string.
5518 * @param __s C string containing characters to locate.
5519 * @param __pos Index of character to search back from (default end).
5520 * @return Index of last occurrence.
5521 *
5522 * Starting from @a __pos, searches backward for one of the
5523 * characters of @a __s within this string. If found, returns
5524 * the index where it was found. If not found, returns npos.
5525 */
5526 size_type
5527 find_last_of(const _CharT* __s, size_type __pos = npos) const
5528 _GLIBCXX_NOEXCEPTnoexcept
5529 {
5530 __glibcxx_requires_string(__s);
5531 return this->find_last_of(__s, __pos, traits_type::length(__s));
5532 }
5533
5534 /**
5535 * @brief Find last position of a character.
5536 * @param __c Character to locate.
5537 * @param __pos Index of character to search back from (default end).
5538 * @return Index of last occurrence.
5539 *
5540 * Starting from @a __pos, searches backward for @a __c within
5541 * this string. If found, returns the index where it was
5542 * found. If not found, returns npos.
5543 *
5544 * Note: equivalent to rfind(__c, __pos).
5545 */
5546 size_type
5547 find_last_of(_CharT __c, size_type __pos = npos) const _GLIBCXX_NOEXCEPTnoexcept
5548 { return this->rfind(__c, __pos); }
5549
5550#if __cplusplus201402L >= 201703L
5551 /**
5552 * @brief Find last position of a character of string.
5553 * @param __svt An object convertible to string_view containing
5554 * characters to locate.
5555 * @param __pos Index of character to search back from (default end).
5556 * @return Index of last occurrence.
5557 */
5558 template<typename _Tp>
5559 _If_sv<_Tp, size_type>
5560 find_last_of(const _Tp& __svt, size_type __pos = npos) const
5561 noexcept(is_same<_Tp, __sv_type>::value)
5562 {
5563 __sv_type __sv = __svt;
5564 return this->find_last_of(__sv.data(), __pos, __sv.size());
5565 }
5566#endif // C++17
5567
5568 /**
5569 * @brief Find position of a character not in string.
5570 * @param __str String containing characters to avoid.
5571 * @param __pos Index of character to search from (default 0).
5572 * @return Index of first occurrence.
5573 *
5574 * Starting from @a __pos, searches forward for a character not contained
5575 * in @a __str within this string. If found, returns the index where it
5576 * was found. If not found, returns npos.
5577 */
5578 size_type
5579 find_first_not_of(const basic_string& __str, size_type __pos = 0) const
5580 _GLIBCXX_NOEXCEPTnoexcept
5581 { return this->find_first_not_of(__str.data(), __pos, __str.size()); }
5582
5583 /**
5584 * @brief Find position of a character not in C substring.
5585 * @param __s C string containing characters to avoid.
5586 * @param __pos Index of character to search from.
5587 * @param __n Number of characters from __s to consider.
5588 * @return Index of first occurrence.
5589 *
5590 * Starting from @a __pos, searches forward for a character not
5591 * contained in the first @a __n characters of @a __s within
5592 * this string. If found, returns the index where it was
5593 * found. If not found, returns npos.
5594 */
5595 size_type
5596 find_first_not_of(const _CharT* __s, size_type __pos,
5597 size_type __n) const _GLIBCXX_NOEXCEPTnoexcept;
5598
5599 /**
5600 * @brief Find position of a character not in C string.
5601 * @param __s C string containing characters to avoid.
5602 * @param __pos Index of character to search from (default 0).
5603 * @return Index of first occurrence.
5604 *
5605 * Starting from @a __pos, searches forward for a character not
5606 * contained in @a __s within this string. If found, returns
5607 * the index where it was found. If not found, returns npos.
5608 */
5609 size_type
5610 find_first_not_of(const _CharT* __s, size_type __pos = 0) const
5611 _GLIBCXX_NOEXCEPTnoexcept
5612 {
5613 __glibcxx_requires_string(__s);
5614 return this->find_first_not_of(__s, __pos, traits_type::length(__s));
5615 }
5616
5617 /**
5618 * @brief Find position of a different character.
5619 * @param __c Character to avoid.
5620 * @param __pos Index of character to search from (default 0).
5621 * @return Index of first occurrence.
5622 *
5623 * Starting from @a __pos, searches forward for a character
5624 * other than @a __c within this string. If found, returns the
5625 * index where it was found. If not found, returns npos.
5626 */
5627 size_type
5628 find_first_not_of(_CharT __c, size_type __pos = 0) const
5629 _GLIBCXX_NOEXCEPTnoexcept;
5630
5631#if __cplusplus201402L >= 201703L
5632 /**
5633 * @brief Find position of a character not in a string_view.
5634 * @param __svt An object convertible to string_view containing
5635 * characters to avoid.
5636 * @param __pos Index of character to search from (default 0).
5637 * @return Index of first occurrence.
5638 */
5639 template<typename _Tp>
5640 _If_sv<_Tp, size_type>
5641 find_first_not_of(const _Tp& __svt, size_type __pos = 0) const
5642 noexcept(is_same<_Tp, __sv_type>::value)
5643 {
5644 __sv_type __sv = __svt;
5645 return this->find_first_not_of(__sv.data(), __pos, __sv.size());
5646 }
5647#endif // C++17
5648
5649 /**
5650 * @brief Find last position of a character not in string.
5651 * @param __str String containing characters to avoid.
5652 * @param __pos Index of character to search back from (default end).
5653 * @return Index of last occurrence.
5654 *
5655 * Starting from @a __pos, searches backward for a character
5656 * not contained in @a __str within this string. If found,
5657 * returns the index where it was found. If not found, returns
5658 * npos.
5659 */
5660 size_type
5661 find_last_not_of(const basic_string& __str, size_type __pos = npos) const
5662 _GLIBCXX_NOEXCEPTnoexcept
5663 { return this->find_last_not_of(__str.data(), __pos, __str.size()); }
5664
5665 /**
5666 * @brief Find last position of a character not in C substring.
5667 * @param __s C string containing characters to avoid.
5668 * @param __pos Index of character to search back from.
5669 * @param __n Number of characters from s to consider.
5670 * @return Index of last occurrence.
5671 *
5672 * Starting from @a __pos, searches backward for a character not
5673 * contained in the first @a __n characters of @a __s within this string.
5674 * If found, returns the index where it was found. If not found,
5675 * returns npos.
5676 */
5677 size_type
5678 find_last_not_of(const _CharT* __s, size_type __pos,
5679 size_type __n) const _GLIBCXX_NOEXCEPTnoexcept;
5680 /**
5681 * @brief Find last position of a character not in C string.
5682 * @param __s C string containing characters to avoid.
5683 * @param __pos Index of character to search back from (default end).
5684 * @return Index of last occurrence.
5685 *
5686 * Starting from @a __pos, searches backward for a character
5687 * not contained in @a __s within this string. If found,
5688 * returns the index where it was found. If not found, returns
5689 * npos.
5690 */
5691 size_type
5692 find_last_not_of(const _CharT* __s, size_type __pos = npos) const
5693 _GLIBCXX_NOEXCEPTnoexcept
5694 {
5695 __glibcxx_requires_string(__s);
5696 return this->find_last_not_of(__s, __pos, traits_type::length(__s));
5697 }
5698
5699 /**
5700 * @brief Find last position of a different character.
5701 * @param __c Character to avoid.
5702 * @param __pos Index of character to search back from (default end).
5703 * @return Index of last occurrence.
5704 *
5705 * Starting from @a __pos, searches backward for a character other than
5706 * @a __c within this string. If found, returns the index where it was
5707 * found. If not found, returns npos.
5708 */
5709 size_type
5710 find_last_not_of(_CharT __c, size_type __pos = npos) const
5711 _GLIBCXX_NOEXCEPTnoexcept;
5712
5713#if __cplusplus201402L >= 201703L
5714 /**
5715 * @brief Find last position of a character not in a string_view.
5716 * @param __svt An object convertible to string_view containing
5717 * characters to avoid.
5718 * @param __pos Index of character to search back from (default end).
5719 * @return Index of last occurrence.
5720 */
5721 template<typename _Tp>
5722 _If_sv<_Tp, size_type>
5723 find_last_not_of(const _Tp& __svt, size_type __pos = npos) const
5724 noexcept(is_same<_Tp, __sv_type>::value)
5725 {
5726 __sv_type __sv = __svt;
5727 return this->find_last_not_of(__sv.data(), __pos, __sv.size());
5728 }
5729#endif // C++17
5730
5731 /**
5732 * @brief Get a substring.
5733 * @param __pos Index of first character (default 0).
5734 * @param __n Number of characters in substring (default remainder).
5735 * @return The new string.
5736 * @throw std::out_of_range If __pos > size().
5737 *
5738 * Construct and return a new string using the @a __n
5739 * characters starting at @a __pos. If the string is too
5740 * short, use the remainder of the characters. If @a __pos is
5741 * beyond the end of the string, out_of_range is thrown.
5742 */
5743 basic_string
5744 substr(size_type __pos = 0, size_type __n = npos) const
5745 { return basic_string(*this,
5746 _M_check(__pos, "basic_string::substr"), __n); }
5747
5748 /**
5749 * @brief Compare to a string.
5750 * @param __str String to compare against.
5751 * @return Integer < 0, 0, or > 0.
5752 *
5753 * Returns an integer < 0 if this string is ordered before @a
5754 * __str, 0 if their values are equivalent, or > 0 if this
5755 * string is ordered after @a __str. Determines the effective
5756 * length rlen of the strings to compare as the smallest of
5757 * size() and str.size(). The function then compares the two
5758 * strings by calling traits::compare(data(), str.data(),rlen).
5759 * If the result of the comparison is nonzero returns it,
5760 * otherwise the shorter one is ordered first.
5761 */
5762 int
5763 compare(const basic_string& __str) const
5764 {
5765 const size_type __size = this->size();
5766 const size_type __osize = __str.size();
5767 const size_type __len = std::min(__size, __osize);
5768
5769 int __r = traits_type::compare(_M_data(), __str.data(), __len);
5770 if (!__r)
5771 __r = _S_compare(__size, __osize);
5772 return __r;
5773 }
5774
5775#if __cplusplus201402L >= 201703L
5776 /**
5777 * @brief Compare to a string_view.
5778 * @param __svt An object convertible to string_view to compare against.
5779 * @return Integer < 0, 0, or > 0.
5780 */
5781 template<typename _Tp>
5782 _If_sv<_Tp, int>
5783 compare(const _Tp& __svt) const
5784 noexcept(is_same<_Tp, __sv_type>::value)
5785 {
5786 __sv_type __sv = __svt;
5787 const size_type __size = this->size();
5788 const size_type __osize = __sv.size();
5789 const size_type __len = std::min(__size, __osize);
5790
5791 int __r = traits_type::compare(_M_data(), __sv.data(), __len);
5792 if (!__r)
5793 __r = _S_compare(__size, __osize);
5794 return __r;
5795 }
5796
5797 /**
5798 * @brief Compare to a string_view.
5799 * @param __pos A position in the string to start comparing from.
5800 * @param __n The number of characters to compare.
5801 * @param __svt An object convertible to string_view to compare
5802 * against.
5803 * @return Integer < 0, 0, or > 0.
5804 */
5805 template<typename _Tp>
5806 _If_sv<_Tp, int>
5807 compare(size_type __pos, size_type __n, const _Tp& __svt) const
5808 noexcept(is_same<_Tp, __sv_type>::value)
5809 {
5810 __sv_type __sv = __svt;
5811 return __sv_type(*this).substr(__pos, __n).compare(__sv);
5812 }
5813
5814 /**
5815 * @brief Compare to a string_view.
5816 * @param __pos1 A position in the string to start comparing from.
5817 * @param __n1 The number of characters to compare.
5818 * @param __svt An object convertible to string_view to compare
5819 * against.
5820 * @param __pos2 A position in the string_view to start comparing from.
5821 * @param __n2 The number of characters to compare.
5822 * @return Integer < 0, 0, or > 0.
5823 */
5824 template<typename _Tp>
5825 _If_sv<_Tp, int>
5826 compare(size_type __pos1, size_type __n1, const _Tp& __svt,
5827 size_type __pos2, size_type __n2 = npos) const
5828 noexcept(is_same<_Tp, __sv_type>::value)
5829 {
5830 __sv_type __sv = __svt;
5831 return __sv_type(*this)
5832 .substr(__pos1, __n1).compare(__sv.substr(__pos2, __n2));
5833 }
5834#endif // C++17
5835
5836 /**
5837 * @brief Compare substring to a string.
5838 * @param __pos Index of first character of substring.
5839 * @param __n Number of characters in substring.
5840 * @param __str String to compare against.
5841 * @return Integer < 0, 0, or > 0.
5842 *
5843 * Form the substring of this string from the @a __n characters
5844 * starting at @a __pos. Returns an integer < 0 if the
5845 * substring is ordered before @a __str, 0 if their values are
5846 * equivalent, or > 0 if the substring is ordered after @a
5847 * __str. Determines the effective length rlen of the strings
5848 * to compare as the smallest of the length of the substring
5849 * and @a __str.size(). The function then compares the two
5850 * strings by calling
5851 * traits::compare(substring.data(),str.data(),rlen). If the
5852 * result of the comparison is nonzero returns it, otherwise
5853 * the shorter one is ordered first.
5854 */
5855 int
5856 compare(size_type __pos, size_type __n, const basic_string& __str) const;
5857
5858 /**
5859 * @brief Compare substring to a substring.
5860 * @param __pos1 Index of first character of substring.
5861 * @param __n1 Number of characters in substring.
5862 * @param __str String to compare against.
5863 * @param __pos2 Index of first character of substring of str.
5864 * @param __n2 Number of characters in substring of str.
5865 * @return Integer < 0, 0, or > 0.
5866 *
5867 * Form the substring of this string from the @a __n1
5868 * characters starting at @a __pos1. Form the substring of @a
5869 * __str from the @a __n2 characters starting at @a __pos2.
5870 * Returns an integer < 0 if this substring is ordered before
5871 * the substring of @a __str, 0 if their values are equivalent,
5872 * or > 0 if this substring is ordered after the substring of
5873 * @a __str. Determines the effective length rlen of the
5874 * strings to compare as the smallest of the lengths of the
5875 * substrings. The function then compares the two strings by
5876 * calling
5877 * traits::compare(substring.data(),str.substr(pos2,n2).data(),rlen).
5878 * If the result of the comparison is nonzero returns it,
5879 * otherwise the shorter one is ordered first.
5880 */
5881 int
5882 compare(size_type __pos1, size_type __n1, const basic_string& __str,
5883 size_type __pos2, size_type __n2 = npos) const;
5884
5885 /**
5886 * @brief Compare to a C string.
5887 * @param __s C string to compare against.
5888 * @return Integer < 0, 0, or > 0.
5889 *
5890 * Returns an integer < 0 if this string is ordered before @a __s, 0 if
5891 * their values are equivalent, or > 0 if this string is ordered after
5892 * @a __s. Determines the effective length rlen of the strings to
5893 * compare as the smallest of size() and the length of a string
5894 * constructed from @a __s. The function then compares the two strings
5895 * by calling traits::compare(data(),s,rlen). If the result of the
5896 * comparison is nonzero returns it, otherwise the shorter one is
5897 * ordered first.
5898 */
5899 int
5900 compare(const _CharT* __s) const _GLIBCXX_NOEXCEPTnoexcept;
5901
5902 // _GLIBCXX_RESOLVE_LIB_DEFECTS
5903 // 5 String::compare specification questionable
5904 /**
5905 * @brief Compare substring to a C string.
5906 * @param __pos Index of first character of substring.
5907 * @param __n1 Number of characters in substring.
5908 * @param __s C string to compare against.
5909 * @return Integer < 0, 0, or > 0.
5910 *
5911 * Form the substring of this string from the @a __n1
5912 * characters starting at @a pos. Returns an integer < 0 if
5913 * the substring is ordered before @a __s, 0 if their values
5914 * are equivalent, or > 0 if the substring is ordered after @a
5915 * __s. Determines the effective length rlen of the strings to
5916 * compare as the smallest of the length of the substring and
5917 * the length of a string constructed from @a __s. The
5918 * function then compares the two string by calling
5919 * traits::compare(substring.data(),__s,rlen). If the result of
5920 * the comparison is nonzero returns it, otherwise the shorter
5921 * one is ordered first.
5922 */
5923 int
5924 compare(size_type __pos, size_type __n1, const _CharT* __s) const;
5925
5926 /**
5927 * @brief Compare substring against a character %array.
5928 * @param __pos Index of first character of substring.
5929 * @param __n1 Number of characters in substring.
5930 * @param __s character %array to compare against.
5931 * @param __n2 Number of characters of s.
5932 * @return Integer < 0, 0, or > 0.
5933 *
5934 * Form the substring of this string from the @a __n1
5935 * characters starting at @a __pos. Form a string from the
5936 * first @a __n2 characters of @a __s. Returns an integer < 0
5937 * if this substring is ordered before the string from @a __s,
5938 * 0 if their values are equivalent, or > 0 if this substring
5939 * is ordered after the string from @a __s. Determines the
5940 * effective length rlen of the strings to compare as the
5941 * smallest of the length of the substring and @a __n2. The
5942 * function then compares the two strings by calling
5943 * traits::compare(substring.data(),s,rlen). If the result of
5944 * the comparison is nonzero returns it, otherwise the shorter
5945 * one is ordered first.
5946 *
5947 * NB: s must have at least n2 characters, &apos;\\0&apos; has
5948 * no special meaning.
5949 */
5950 int
5951 compare(size_type __pos, size_type __n1, const _CharT* __s,
5952 size_type __n2) const;
5953
5954#if __cplusplus201402L > 201703L
5955 bool
5956 starts_with(basic_string_view<_CharT, _Traits> __x) const noexcept
5957 { return __sv_type(this->data(), this->size()).starts_with(__x); }
5958
5959 bool
5960 starts_with(_CharT __x) const noexcept
5961 { return __sv_type(this->data(), this->size()).starts_with(__x); }
5962
5963 bool
5964 starts_with(const _CharT* __x) const noexcept
5965 { return __sv_type(this->data(), this->size()).starts_with(__x); }
5966
5967 bool
5968 ends_with(basic_string_view<_CharT, _Traits> __x) const noexcept
5969 { return __sv_type(this->data(), this->size()).ends_with(__x); }
5970
5971 bool
5972 ends_with(_CharT __x) const noexcept
5973 { return __sv_type(this->data(), this->size()).ends_with(__x); }
5974
5975 bool
5976 ends_with(const _CharT* __x) const noexcept
5977 { return __sv_type(this->data(), this->size()).ends_with(__x); }
5978#endif // C++20
5979
5980# ifdef _GLIBCXX_TM_TS_INTERNAL
5981 friend void
5982 ::_txnal_cow_string_C1_for_exceptions(void* that, const char* s,
5983 void* exc);
5984 friend const char*
5985 ::_txnal_cow_string_c_str(const void *that);
5986 friend void
5987 ::_txnal_cow_string_D1(void *that);
5988 friend void
5989 ::_txnal_cow_string_D1_commit(void *that);
5990# endif
5991 };
5992#endif // !_GLIBCXX_USE_CXX11_ABI
5993
5994#if __cpp_deduction_guides >= 201606
5995_GLIBCXX_BEGIN_NAMESPACE_CXX11namespace __cxx11 {
5996 template<typename _InputIterator, typename _CharT
5997 = typename iterator_traits<_InputIterator>::value_type,
5998 typename _Allocator = allocator<_CharT>,
5999 typename = _RequireInputIter<_InputIterator>,
6000 typename = _RequireAllocator<_Allocator>>
6001 basic_string(_InputIterator, _InputIterator, _Allocator = _Allocator())
6002 -> basic_string<_CharT, char_traits<_CharT>, _Allocator>;
6003
6004 // _GLIBCXX_RESOLVE_LIB_DEFECTS
6005 // 3075. basic_string needs deduction guides from basic_string_view
6006 template<typename _CharT, typename _Traits,
6007 typename _Allocator = allocator<_CharT>,
6008 typename = _RequireAllocator<_Allocator>>
6009 basic_string(basic_string_view<_CharT, _Traits>, const _Allocator& = _Allocator())
6010 -> basic_string<_CharT, _Traits, _Allocator>;
6011
6012 template<typename _CharT, typename _Traits,
6013 typename _Allocator = allocator<_CharT>,
6014 typename = _RequireAllocator<_Allocator>>
6015 basic_string(basic_string_view<_CharT, _Traits>,
6016 typename basic_string<_CharT, _Traits, _Allocator>::size_type,
6017 typename basic_string<_CharT, _Traits, _Allocator>::size_type,
6018 const _Allocator& = _Allocator())
6019 -> basic_string<_CharT, _Traits, _Allocator>;
6020_GLIBCXX_END_NAMESPACE_CXX11}
6021#endif
6022
6023 // operator+
6024 /**
6025 * @brief Concatenate two strings.
6026 * @param __lhs First string.
6027 * @param __rhs Last string.
6028 * @return New string with value of @a __lhs followed by @a __rhs.
6029 */
6030 template<typename _CharT, typename _Traits, typename _Alloc>
6031 basic_string<_CharT, _Traits, _Alloc>
6032 operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6033 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6034 {
6035 basic_string<_CharT, _Traits, _Alloc> __str(__lhs);
6036 __str.append(__rhs);
6037 return __str;
6038 }
6039
6040 /**
6041 * @brief Concatenate C string and string.
6042 * @param __lhs First string.
6043 * @param __rhs Last string.
6044 * @return New string with value of @a __lhs followed by @a __rhs.
6045 */
6046 template<typename _CharT, typename _Traits, typename _Alloc>
6047 basic_string<_CharT,_Traits,_Alloc>
6048 operator+(const _CharT* __lhs,
6049 const basic_string<_CharT,_Traits,_Alloc>& __rhs);
6050
6051 /**
6052 * @brief Concatenate character and string.
6053 * @param __lhs First string.
6054 * @param __rhs Last string.
6055 * @return New string with @a __lhs followed by @a __rhs.
6056 */
6057 template<typename _CharT, typename _Traits, typename _Alloc>
6058 basic_string<_CharT,_Traits,_Alloc>
6059 operator+(_CharT __lhs, const basic_string<_CharT,_Traits,_Alloc>& __rhs);
6060
6061 /**
6062 * @brief Concatenate string and C string.
6063 * @param __lhs First string.
6064 * @param __rhs Last string.
6065 * @return New string with @a __lhs followed by @a __rhs.
6066 */
6067 template<typename _CharT, typename _Traits, typename _Alloc>
6068 inline basic_string<_CharT, _Traits, _Alloc>
6069 operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6070 const _CharT* __rhs)
6071 {
6072 basic_string<_CharT, _Traits, _Alloc> __str(__lhs);
6073 __str.append(__rhs);
6074 return __str;
6075 }
6076
6077 /**
6078 * @brief Concatenate string and character.
6079 * @param __lhs First string.
6080 * @param __rhs Last string.
6081 * @return New string with @a __lhs followed by @a __rhs.
6082 */
6083 template<typename _CharT, typename _Traits, typename _Alloc>
6084 inline basic_string<_CharT, _Traits, _Alloc>
6085 operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs, _CharT __rhs)
6086 {
6087 typedef basic_string<_CharT, _Traits, _Alloc> __string_type;
6088 typedef typename __string_type::size_type __size_type;
6089 __string_type __str(__lhs);
6090 __str.append(__size_type(1), __rhs);
6091 return __str;
6092 }
6093
6094#if __cplusplus201402L >= 201103L
6095 template<typename _CharT, typename _Traits, typename _Alloc>
6096 inline basic_string<_CharT, _Traits, _Alloc>
6097 operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
6098 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6099 { return std::move(__lhs.append(__rhs)); }
6100
6101 template<typename _CharT, typename _Traits, typename _Alloc>
6102 inline basic_string<_CharT, _Traits, _Alloc>
6103 operator+(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6104 basic_string<_CharT, _Traits, _Alloc>&& __rhs)
6105 { return std::move(__rhs.insert(0, __lhs)); }
6106
6107 template<typename _CharT, typename _Traits, typename _Alloc>
6108 inline basic_string<_CharT, _Traits, _Alloc>
6109 operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
6110 basic_string<_CharT, _Traits, _Alloc>&& __rhs)
6111 {
6112#if _GLIBCXX_USE_CXX11_ABI1
6113 using _Alloc_traits = allocator_traits<_Alloc>;
6114 bool __use_rhs = false;
6115 if _GLIBCXX17_CONSTEXPR (typename _Alloc_traits::is_always_equal{})
6116 __use_rhs = true;
6117 else if (__lhs.get_allocator() == __rhs.get_allocator())
6118 __use_rhs = true;
6119 if (__use_rhs)
6120#endif
6121 {
6122 const auto __size = __lhs.size() + __rhs.size();
6123 if (__size > __lhs.capacity() && __size <= __rhs.capacity())
6124 return std::move(__rhs.insert(0, __lhs));
6125 }
6126 return std::move(__lhs.append(__rhs));
6127 }
6128
6129 template<typename _CharT, typename _Traits, typename _Alloc>
6130 inline basic_string<_CharT, _Traits, _Alloc>
6131 operator+(const _CharT* __lhs,
6132 basic_string<_CharT, _Traits, _Alloc>&& __rhs)
6133 { return std::move(__rhs.insert(0, __lhs)); }
6134
6135 template<typename _CharT, typename _Traits, typename _Alloc>
6136 inline basic_string<_CharT, _Traits, _Alloc>
6137 operator+(_CharT __lhs,
6138 basic_string<_CharT, _Traits, _Alloc>&& __rhs)
6139 { return std::move(__rhs.insert(0, 1, __lhs)); }
6140
6141 template<typename _CharT, typename _Traits, typename _Alloc>
6142 inline basic_string<_CharT, _Traits, _Alloc>
6143 operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
6144 const _CharT* __rhs)
6145 { return std::move(__lhs.append(__rhs)); }
6146
6147 template<typename _CharT, typename _Traits, typename _Alloc>
6148 inline basic_string<_CharT, _Traits, _Alloc>
6149 operator+(basic_string<_CharT, _Traits, _Alloc>&& __lhs,
6150 _CharT __rhs)
6151 { return std::move(__lhs.append(1, __rhs)); }
6152#endif
6153
6154 // operator ==
6155 /**
6156 * @brief Test equivalence of two strings.
6157 * @param __lhs First string.
6158 * @param __rhs Second string.
6159 * @return True if @a __lhs.compare(@a __rhs) == 0. False otherwise.
6160 */
6161 template<typename _CharT, typename _Traits, typename _Alloc>
6162 inline bool
6163 operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6164 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6165 _GLIBCXX_NOEXCEPTnoexcept
6166 { return __lhs.compare(__rhs) == 0; }
6167
6168 template<typename _CharT>
6169 inline
6170 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, bool>::__type
6171 operator==(const basic_string<_CharT>& __lhs,
6172 const basic_string<_CharT>& __rhs) _GLIBCXX_NOEXCEPTnoexcept
6173 { return (__lhs.size() == __rhs.size()
6174 && !std::char_traits<_CharT>::compare(__lhs.data(), __rhs.data(),
6175 __lhs.size())); }
6176
6177 /**
6178 * @brief Test equivalence of string and C string.
6179 * @param __lhs String.
6180 * @param __rhs C string.
6181 * @return True if @a __lhs.compare(@a __rhs) == 0. False otherwise.
6182 */
6183 template<typename _CharT, typename _Traits, typename _Alloc>
6184 inline bool
6185 operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6186 const _CharT* __rhs)
6187 { return __lhs.compare(__rhs) == 0; }
6188
6189#if __cpp_lib_three_way_comparison
6190 /**
6191 * @brief Three-way comparison of a string and a C string.
6192 * @param __lhs A string.
6193 * @param __rhs A null-terminated string.
6194 * @return A value indicating whether `__lhs` is less than, equal to,
6195 * greater than, or incomparable with `__rhs`.
6196 */
6197 template<typename _CharT, typename _Traits, typename _Alloc>
6198 inline auto
6199 operator<=>(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6200 const basic_string<_CharT, _Traits, _Alloc>& __rhs) noexcept
6201 -> decltype(__detail::__char_traits_cmp_cat<_Traits>(0))
6202 { return __detail::__char_traits_cmp_cat<_Traits>(__lhs.compare(__rhs)); }
6203
6204 /**
6205 * @brief Three-way comparison of a string and a C string.
6206 * @param __lhs A string.
6207 * @param __rhs A null-terminated string.
6208 * @return A value indicating whether `__lhs` is less than, equal to,
6209 * greater than, or incomparable with `__rhs`.
6210 */
6211 template<typename _CharT, typename _Traits, typename _Alloc>
6212 inline auto
6213 operator<=>(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6214 const _CharT* __rhs) noexcept
6215 -> decltype(__detail::__char_traits_cmp_cat<_Traits>(0))
6216 { return __detail::__char_traits_cmp_cat<_Traits>(__lhs.compare(__rhs)); }
6217#else
6218 /**
6219 * @brief Test equivalence of C string and string.
6220 * @param __lhs C string.
6221 * @param __rhs String.
6222 * @return True if @a __rhs.compare(@a __lhs) == 0. False otherwise.
6223 */
6224 template<typename _CharT, typename _Traits, typename _Alloc>
6225 inline bool
6226 operator==(const _CharT* __lhs,
6227 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6228 { return __rhs.compare(__lhs) == 0; }
6229
6230 // operator !=
6231 /**
6232 * @brief Test difference of two strings.
6233 * @param __lhs First string.
6234 * @param __rhs Second string.
6235 * @return True if @a __lhs.compare(@a __rhs) != 0. False otherwise.
6236 */
6237 template<typename _CharT, typename _Traits, typename _Alloc>
6238 inline bool
6239 operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6240 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6241 _GLIBCXX_NOEXCEPTnoexcept
6242 { return !(__lhs == __rhs); }
6243
6244 /**
6245 * @brief Test difference of C string and string.
6246 * @param __lhs C string.
6247 * @param __rhs String.
6248 * @return True if @a __rhs.compare(@a __lhs) != 0. False otherwise.
6249 */
6250 template<typename _CharT, typename _Traits, typename _Alloc>
6251 inline bool
6252 operator!=(const _CharT* __lhs,
6253 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6254 { return !(__lhs == __rhs); }
6255
6256 /**
6257 * @brief Test difference of string and C string.
6258 * @param __lhs String.
6259 * @param __rhs C string.
6260 * @return True if @a __lhs.compare(@a __rhs) != 0. False otherwise.
6261 */
6262 template<typename _CharT, typename _Traits, typename _Alloc>
6263 inline bool
6264 operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6265 const _CharT* __rhs)
6266 { return !(__lhs == __rhs); }
6267
6268 // operator <
6269 /**
6270 * @brief Test if string precedes string.
6271 * @param __lhs First string.
6272 * @param __rhs Second string.
6273 * @return True if @a __lhs precedes @a __rhs. False otherwise.
6274 */
6275 template<typename _CharT, typename _Traits, typename _Alloc>
6276 inline bool
6277 operator<(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6278 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6279 _GLIBCXX_NOEXCEPTnoexcept
6280 { return __lhs.compare(__rhs) < 0; }
6281
6282 /**
6283 * @brief Test if string precedes C string.
6284 * @param __lhs String.
6285 * @param __rhs C string.
6286 * @return True if @a __lhs precedes @a __rhs. False otherwise.
6287 */
6288 template<typename _CharT, typename _Traits, typename _Alloc>
6289 inline bool
6290 operator<(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6291 const _CharT* __rhs)
6292 { return __lhs.compare(__rhs) < 0; }
6293
6294 /**
6295 * @brief Test if C string precedes string.
6296 * @param __lhs C string.
6297 * @param __rhs String.
6298 * @return True if @a __lhs precedes @a __rhs. False otherwise.
6299 */
6300 template<typename _CharT, typename _Traits, typename _Alloc>
6301 inline bool
6302 operator<(const _CharT* __lhs,
6303 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6304 { return __rhs.compare(__lhs) > 0; }
6305
6306 // operator >
6307 /**
6308 * @brief Test if string follows string.
6309 * @param __lhs First string.
6310 * @param __rhs Second string.
6311 * @return True if @a __lhs follows @a __rhs. False otherwise.
6312 */
6313 template<typename _CharT, typename _Traits, typename _Alloc>
6314 inline bool
6315 operator>(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6316 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6317 _GLIBCXX_NOEXCEPTnoexcept
6318 { return __lhs.compare(__rhs) > 0; }
6319
6320 /**
6321 * @brief Test if string follows C string.
6322 * @param __lhs String.
6323 * @param __rhs C string.
6324 * @return True if @a __lhs follows @a __rhs. False otherwise.
6325 */
6326 template<typename _CharT, typename _Traits, typename _Alloc>
6327 inline bool
6328 operator>(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6329 const _CharT* __rhs)
6330 { return __lhs.compare(__rhs) > 0; }
6331
6332 /**
6333 * @brief Test if C string follows string.
6334 * @param __lhs C string.
6335 * @param __rhs String.
6336 * @return True if @a __lhs follows @a __rhs. False otherwise.
6337 */
6338 template<typename _CharT, typename _Traits, typename _Alloc>
6339 inline bool
6340 operator>(const _CharT* __lhs,
6341 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6342 { return __rhs.compare(__lhs) < 0; }
6343
6344 // operator <=
6345 /**
6346 * @brief Test if string doesn't follow string.
6347 * @param __lhs First string.
6348 * @param __rhs Second string.
6349 * @return True if @a __lhs doesn't follow @a __rhs. False otherwise.
6350 */
6351 template<typename _CharT, typename _Traits, typename _Alloc>
6352 inline bool
6353 operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6354 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6355 _GLIBCXX_NOEXCEPTnoexcept
6356 { return __lhs.compare(__rhs) <= 0; }
6357
6358 /**
6359 * @brief Test if string doesn't follow C string.
6360 * @param __lhs String.
6361 * @param __rhs C string.
6362 * @return True if @a __lhs doesn't follow @a __rhs. False otherwise.
6363 */
6364 template<typename _CharT, typename _Traits, typename _Alloc>
6365 inline bool
6366 operator<=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6367 const _CharT* __rhs)
6368 { return __lhs.compare(__rhs) <= 0; }
6369
6370 /**
6371 * @brief Test if C string doesn't follow string.
6372 * @param __lhs C string.
6373 * @param __rhs String.
6374 * @return True if @a __lhs doesn't follow @a __rhs. False otherwise.
6375 */
6376 template<typename _CharT, typename _Traits, typename _Alloc>
6377 inline bool
6378 operator<=(const _CharT* __lhs,
6379 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6380 { return __rhs.compare(__lhs) >= 0; }
6381
6382 // operator >=
6383 /**
6384 * @brief Test if string doesn't precede string.
6385 * @param __lhs First string.
6386 * @param __rhs Second string.
6387 * @return True if @a __lhs doesn't precede @a __rhs. False otherwise.
6388 */
6389 template<typename _CharT, typename _Traits, typename _Alloc>
6390 inline bool
6391 operator>=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6392 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6393 _GLIBCXX_NOEXCEPTnoexcept
6394 { return __lhs.compare(__rhs) >= 0; }
6395
6396 /**
6397 * @brief Test if string doesn't precede C string.
6398 * @param __lhs String.
6399 * @param __rhs C string.
6400 * @return True if @a __lhs doesn't precede @a __rhs. False otherwise.
6401 */
6402 template<typename _CharT, typename _Traits, typename _Alloc>
6403 inline bool
6404 operator>=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
6405 const _CharT* __rhs)
6406 { return __lhs.compare(__rhs) >= 0; }
6407
6408 /**
6409 * @brief Test if C string doesn't precede string.
6410 * @param __lhs C string.
6411 * @param __rhs String.
6412 * @return True if @a __lhs doesn't precede @a __rhs. False otherwise.
6413 */
6414 template<typename _CharT, typename _Traits, typename _Alloc>
6415 inline bool
6416 operator>=(const _CharT* __lhs,
6417 const basic_string<_CharT, _Traits, _Alloc>& __rhs)
6418 { return __rhs.compare(__lhs) <= 0; }
6419#endif // three-way comparison
6420
6421 /**
6422 * @brief Swap contents of two strings.
6423 * @param __lhs First string.
6424 * @param __rhs Second string.
6425 *
6426 * Exchanges the contents of @a __lhs and @a __rhs in constant time.
6427 */
6428 template<typename _CharT, typename _Traits, typename _Alloc>
6429 inline void
6430 swap(basic_string<_CharT, _Traits, _Alloc>& __lhs,
6431 basic_string<_CharT, _Traits, _Alloc>& __rhs)
6432 _GLIBCXX_NOEXCEPT_IF(noexcept(__lhs.swap(__rhs)))noexcept(noexcept(__lhs.swap(__rhs)))
6433 { __lhs.swap(__rhs); }
6434
6435
6436 /**
6437 * @brief Read stream into a string.
6438 * @param __is Input stream.
6439 * @param __str Buffer to store into.
6440 * @return Reference to the input stream.
6441 *
6442 * Stores characters from @a __is into @a __str until whitespace is
6443 * found, the end of the stream is encountered, or str.max_size()
6444 * is reached. If is.width() is non-zero, that is the limit on the
6445 * number of characters stored into @a __str. Any previous
6446 * contents of @a __str are erased.
6447 */
6448 template<typename _CharT, typename _Traits, typename _Alloc>
6449 basic_istream<_CharT, _Traits>&
6450 operator>>(basic_istream<_CharT, _Traits>& __is,
6451 basic_string<_CharT, _Traits, _Alloc>& __str);
6452
6453 template<>
6454 basic_istream<char>&
6455 operator>>(basic_istream<char>& __is, basic_string<char>& __str);
6456
6457 /**
6458 * @brief Write string to a stream.
6459 * @param __os Output stream.
6460 * @param __str String to write out.
6461 * @return Reference to the output stream.
6462 *
6463 * Output characters of @a __str into os following the same rules as for
6464 * writing a C string.
6465 */
6466 template<typename _CharT, typename _Traits, typename _Alloc>
6467 inline basic_ostream<_CharT, _Traits>&
6468 operator<<(basic_ostream<_CharT, _Traits>& __os,
6469 const basic_string<_CharT, _Traits, _Alloc>& __str)
6470 {
6471 // _GLIBCXX_RESOLVE_LIB_DEFECTS
6472 // 586. string inserter not a formatted function
6473 return __ostream_insert(__os, __str.data(), __str.size());
6474 }
6475
6476 /**
6477 * @brief Read a line from stream into a string.
6478 * @param __is Input stream.
6479 * @param __str Buffer to store into.
6480 * @param __delim Character marking end of line.
6481 * @return Reference to the input stream.
6482 *
6483 * Stores characters from @a __is into @a __str until @a __delim is
6484 * found, the end of the stream is encountered, or str.max_size()
6485 * is reached. Any previous contents of @a __str are erased. If
6486 * @a __delim is encountered, it is extracted but not stored into
6487 * @a __str.
6488 */
6489 template<typename _CharT, typename _Traits, typename _Alloc>
6490 basic_istream<_CharT, _Traits>&
6491 getline(basic_istream<_CharT, _Traits>& __is,
6492 basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim);
6493
6494 /**
6495 * @brief Read a line from stream into a string.
6496 * @param __is Input stream.
6497 * @param __str Buffer to store into.
6498 * @return Reference to the input stream.
6499 *
6500 * Stores characters from is into @a __str until &apos;\n&apos; is
6501 * found, the end of the stream is encountered, or str.max_size()
6502 * is reached. Any previous contents of @a __str are erased. If
6503 * end of line is encountered, it is extracted but not stored into
6504 * @a __str.
6505 */
6506 template<typename _CharT, typename _Traits, typename _Alloc>
6507 inline basic_istream<_CharT, _Traits>&
6508 getline(basic_istream<_CharT, _Traits>& __is,
6509 basic_string<_CharT, _Traits, _Alloc>& __str)
6510 { return std::getline(__is, __str, __is.widen('\n')); }
6511
6512#if __cplusplus201402L >= 201103L
6513 /// Read a line from an rvalue stream into a string.
6514 template<typename _CharT, typename _Traits, typename _Alloc>
6515 inline basic_istream<_CharT, _Traits>&
6516 getline(basic_istream<_CharT, _Traits>&& __is,
6517 basic_string<_CharT, _Traits, _Alloc>& __str, _CharT __delim)
6518 { return std::getline(__is, __str, __delim); }
6519
6520 /// Read a line from an rvalue stream into a string.
6521 template<typename _CharT, typename _Traits, typename _Alloc>
6522 inline basic_istream<_CharT, _Traits>&
6523 getline(basic_istream<_CharT, _Traits>&& __is,
6524 basic_string<_CharT, _Traits, _Alloc>& __str)
6525 { return std::getline(__is, __str); }
6526#endif
6527
6528 template<>
6529 basic_istream<char>&
6530 getline(basic_istream<char>& __in, basic_string<char>& __str,
6531 char __delim);
6532
6533#ifdef _GLIBCXX_USE_WCHAR_T1
6534 template<>
6535 basic_istream<wchar_t>&
6536 getline(basic_istream<wchar_t>& __in, basic_string<wchar_t>& __str,
6537 wchar_t __delim);
6538#endif
6539
6540_GLIBCXX_END_NAMESPACE_VERSION
6541} // namespace
6542
6543#if __cplusplus201402L >= 201103L
6544
6545#include <ext/string_conversions.h>
6546#include <bits/charconv.h>
6547
6548namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
6549{
6550_GLIBCXX_BEGIN_NAMESPACE_VERSION
6551_GLIBCXX_BEGIN_NAMESPACE_CXX11namespace __cxx11 {
6552
6553#if _GLIBCXX_USE_C99_STDLIB1
6554 // 21.4 Numeric Conversions [string.conversions].
6555 inline int
6556 stoi(const string& __str, size_t* __idx = 0, int __base = 10)
6557 { return __gnu_cxx::__stoa<long, int>(&std::strtol, "stoi", __str.c_str(),
6558 __idx, __base); }
6559
6560 inline long
6561 stol(const string& __str, size_t* __idx = 0, int __base = 10)
6562 { return __gnu_cxx::__stoa(&std::strtol, "stol", __str.c_str(),
6563 __idx, __base); }
6564
6565 inline unsigned long
6566 stoul(const string& __str, size_t* __idx = 0, int __base = 10)
6567 { return __gnu_cxx::__stoa(&std::strtoul, "stoul", __str.c_str(),
6568 __idx, __base); }
6569
6570 inline long long
6571 stoll(const string& __str, size_t* __idx = 0, int __base = 10)
6572 { return __gnu_cxx::__stoa(&std::strtoll, "stoll", __str.c_str(),
6573 __idx, __base); }
6574
6575 inline unsigned long long
6576 stoull(const string& __str, size_t* __idx = 0, int __base = 10)
6577 { return __gnu_cxx::__stoa(&std::strtoull, "stoull", __str.c_str(),
6578 __idx, __base); }
6579
6580 // NB: strtof vs strtod.
6581 inline float
6582 stof(const string& __str, size_t* __idx = 0)
6583 { return __gnu_cxx::__stoa(&std::strtof, "stof", __str.c_str(), __idx); }
6584
6585 inline double
6586 stod(const string& __str, size_t* __idx = 0)
6587 { return __gnu_cxx::__stoa(&std::strtod, "stod", __str.c_str(), __idx); }
6588
6589 inline long double
6590 stold(const string& __str, size_t* __idx = 0)
6591 { return __gnu_cxx::__stoa(&std::strtold, "stold", __str.c_str(), __idx); }
6592#endif // _GLIBCXX_USE_C99_STDLIB
6593
6594 // DR 1261. Insufficent overloads for to_string / to_wstring
6595
6596 inline string
6597 to_string(int __val)
6598 {
6599 const bool __neg = __val < 0;
6600 const unsigned __uval = __neg ? (unsigned)~__val + 1u : __val;
6601 const auto __len = __detail::__to_chars_len(__uval);
6602 string __str(__neg + __len, '-');
6603 __detail::__to_chars_10_impl(&__str[__neg], __len, __uval);
6604 return __str;
6605 }
6606
6607 inline string
6608 to_string(unsigned __val)
6609 {
6610 string __str(__detail::__to_chars_len(__val), '\0');
6611 __detail::__to_chars_10_impl(&__str[0], __str.size(), __val);
6612 return __str;
6613 }
6614
6615 inline string
6616 to_string(long __val)
6617 {
6618 const bool __neg = __val < 0;
6619 const unsigned long __uval = __neg ? (unsigned long)~__val + 1ul : __val;
6620 const auto __len = __detail::__to_chars_len(__uval);
6621 string __str(__neg + __len, '-');
6622 __detail::__to_chars_10_impl(&__str[__neg], __len, __uval);
6623 return __str;
6624 }
6625
6626 inline string
6627 to_string(unsigned long __val)
6628 {
6629 string __str(__detail::__to_chars_len(__val), '\0');
6630 __detail::__to_chars_10_impl(&__str[0], __str.size(), __val);
6631 return __str;
6632 }
6633
6634 inline string
6635 to_string(long long __val)
6636 {
6637 const bool __neg = __val < 0;
6638 const unsigned long long __uval
6639 = __neg ? (unsigned long long)~__val + 1ull : __val;
6640 const auto __len = __detail::__to_chars_len(__uval);
6641 string __str(__neg + __len, '-');
6642 __detail::__to_chars_10_impl(&__str[__neg], __len, __uval);
6643 return __str;
6644 }
6645
6646 inline string
6647 to_string(unsigned long long __val)
6648 {
6649 string __str(__detail::__to_chars_len(__val), '\0');
6650 __detail::__to_chars_10_impl(&__str[0], __str.size(), __val);
6651 return __str;
6652 }
6653
6654#if _GLIBCXX_USE_C99_STDIO1
6655 // NB: (v)snprintf vs sprintf.
6656
6657 inline string
6658 to_string(float __val)
6659 {
6660 const int __n =
6661 __gnu_cxx::__numeric_traits<float>::__max_exponent10 + 20;
6662 return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
6663 "%f", __val);
6664 }
6665
6666 inline string
6667 to_string(double __val)
6668 {
6669 const int __n =
6670 __gnu_cxx::__numeric_traits<double>::__max_exponent10 + 20;
6671 return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
6672 "%f", __val);
6673 }
6674
6675 inline string
6676 to_string(long double __val)
6677 {
6678 const int __n =
6679 __gnu_cxx::__numeric_traits<long double>::__max_exponent10 + 20;
6680 return __gnu_cxx::__to_xstring<string>(&std::vsnprintf, __n,
6681 "%Lf", __val);
6682 }
6683#endif // _GLIBCXX_USE_C99_STDIO
6684
6685#if defined(_GLIBCXX_USE_WCHAR_T1) && _GLIBCXX_USE_C99_WCHAR1
6686 inline int
6687 stoi(const wstring& __str, size_t* __idx = 0, int __base = 10)
6688 { return __gnu_cxx::__stoa<long, int>(&std::wcstol, "stoi", __str.c_str(),
6689 __idx, __base); }
6690
6691 inline long
6692 stol(const wstring& __str, size_t* __idx = 0, int __base = 10)
6693 { return __gnu_cxx::__stoa(&std::wcstol, "stol", __str.c_str(),
6694 __idx, __base); }
6695
6696 inline unsigned long
6697 stoul(const wstring& __str, size_t* __idx = 0, int __base = 10)
6698 { return __gnu_cxx::__stoa(&std::wcstoul, "stoul", __str.c_str(),
6699 __idx, __base); }
6700
6701 inline long long
6702 stoll(const wstring& __str, size_t* __idx = 0, int __base = 10)
6703 { return __gnu_cxx::__stoa(&std::wcstoll, "stoll", __str.c_str(),
6704 __idx, __base); }
6705
6706 inline unsigned long long
6707 stoull(const wstring& __str, size_t* __idx = 0, int __base = 10)
6708 { return __gnu_cxx::__stoa(&std::wcstoull, "stoull", __str.c_str(),
6709 __idx, __base); }
6710
6711 // NB: wcstof vs wcstod.
6712 inline float
6713 stof(const wstring& __str, size_t* __idx = 0)
6714 { return __gnu_cxx::__stoa(&std::wcstof, "stof", __str.c_str(), __idx); }
6715
6716 inline double
6717 stod(const wstring& __str, size_t* __idx = 0)
6718 { return __gnu_cxx::__stoa(&std::wcstod, "stod", __str.c_str(), __idx); }
6719
6720 inline long double
6721 stold(const wstring& __str, size_t* __idx = 0)
6722 { return __gnu_cxx::__stoa(&std::wcstold, "stold", __str.c_str(), __idx); }
6723
6724#ifndef _GLIBCXX_HAVE_BROKEN_VSWPRINTF
6725 // DR 1261.
6726 inline wstring
6727 to_wstring(int __val)
6728 { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, 4 * sizeof(int),
6729 L"%d", __val); }
6730
6731 inline wstring
6732 to_wstring(unsigned __val)
6733 { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
6734 4 * sizeof(unsigned),
6735 L"%u", __val); }
6736
6737 inline wstring
6738 to_wstring(long __val)
6739 { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, 4 * sizeof(long),
6740 L"%ld", __val); }
6741
6742 inline wstring
6743 to_wstring(unsigned long __val)
6744 { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
6745 4 * sizeof(unsigned long),
6746 L"%lu", __val); }
6747
6748 inline wstring
6749 to_wstring(long long __val)
6750 { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
6751 4 * sizeof(long long),
6752 L"%lld", __val); }
6753
6754 inline wstring
6755 to_wstring(unsigned long long __val)
6756 { return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf,
6757 4 * sizeof(unsigned long long),
6758 L"%llu", __val); }
6759
6760 inline wstring
6761 to_wstring(float __val)
6762 {
6763 const int __n =
6764 __gnu_cxx::__numeric_traits<float>::__max_exponent10 + 20;
6765 return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, __n,
6766 L"%f", __val);
6767 }
6768
6769 inline wstring
6770 to_wstring(double __val)
6771 {
6772 const int __n =
6773 __gnu_cxx::__numeric_traits<double>::__max_exponent10 + 20;
6774 return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, __n,
6775 L"%f", __val);
6776 }
6777
6778 inline wstring
6779 to_wstring(long double __val)
6780 {
6781 const int __n =
6782 __gnu_cxx::__numeric_traits<long double>::__max_exponent10 + 20;
6783 return __gnu_cxx::__to_xstring<wstring>(&std::vswprintf, __n,
6784 L"%Lf", __val);
6785 }
6786#endif // _GLIBCXX_HAVE_BROKEN_VSWPRINTF
6787#endif // _GLIBCXX_USE_WCHAR_T && _GLIBCXX_USE_C99_WCHAR
6788
6789_GLIBCXX_END_NAMESPACE_CXX11}
6790_GLIBCXX_END_NAMESPACE_VERSION
6791} // namespace
6792
6793#endif /* C++11 */
6794
6795#if __cplusplus201402L >= 201103L
6796
6797#include <bits/functional_hash.h>
6798
6799namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
6800{
6801_GLIBCXX_BEGIN_NAMESPACE_VERSION
6802
6803 // DR 1182.
6804
6805#ifndef _GLIBCXX_COMPATIBILITY_CXX0X
6806 /// std::hash specialization for string.
6807 template<>
6808 struct hash<string>
6809 : public __hash_base<size_t, string>
6810 {
6811 size_t
6812 operator()(const string& __s) const noexcept
6813 { return std::_Hash_impl::hash(__s.data(), __s.length()); }
6814 };
6815
6816 template<>
6817 struct __is_fast_hash<hash<string>> : std::false_type
6818 { };
6819
6820#ifdef _GLIBCXX_USE_WCHAR_T1
6821 /// std::hash specialization for wstring.
6822 template<>
6823 struct hash<wstring>
6824 : public __hash_base<size_t, wstring>
6825 {
6826 size_t
6827 operator()(const wstring& __s) const noexcept
6828 { return std::_Hash_impl::hash(__s.data(),
6829 __s.length() * sizeof(wchar_t)); }
6830 };
6831
6832 template<>
6833 struct __is_fast_hash<hash<wstring>> : std::false_type
6834 { };
6835#endif
6836#endif /* _GLIBCXX_COMPATIBILITY_CXX0X */
6837
6838#ifdef _GLIBCXX_USE_CHAR8_T
6839 /// std::hash specialization for u8string.
6840 template<>
6841 struct hash<u8string>
6842 : public __hash_base<size_t, u8string>
6843 {
6844 size_t
6845 operator()(const u8string& __s) const noexcept
6846 { return std::_Hash_impl::hash(__s.data(),
6847 __s.length() * sizeof(char8_t)); }
6848 };
6849
6850 template<>
6851 struct __is_fast_hash<hash<u8string>> : std::false_type
6852 { };
6853#endif
6854
6855 /// std::hash specialization for u16string.
6856 template<>
6857 struct hash<u16string>
6858 : public __hash_base<size_t, u16string>
6859 {
6860 size_t
6861 operator()(const u16string& __s) const noexcept
6862 { return std::_Hash_impl::hash(__s.data(),
6863 __s.length() * sizeof(char16_t)); }
6864 };
6865
6866 template<>
6867 struct __is_fast_hash<hash<u16string>> : std::false_type
6868 { };
6869
6870 /// std::hash specialization for u32string.
6871 template<>
6872 struct hash<u32string>
6873 : public __hash_base<size_t, u32string>
6874 {
6875 size_t
6876 operator()(const u32string& __s) const noexcept
6877 { return std::_Hash_impl::hash(__s.data(),
6878 __s.length() * sizeof(char32_t)); }
6879 };
6880
6881 template<>
6882 struct __is_fast_hash<hash<u32string>> : std::false_type
6883 { };
6884
6885#if __cplusplus201402L >= 201402L
6886
6887#define __cpp_lib_string_udls201304 201304
6888
6889 inline namespace literals
6890 {
6891 inline namespace string_literals
6892 {
6893#pragma GCC diagnostic push
6894#pragma GCC diagnostic ignored "-Wliteral-suffix"
6895 _GLIBCXX_DEFAULT_ABI_TAG__attribute ((__abi_tag__ ("cxx11")))
6896 inline basic_string<char>
6897 operator""s(const char* __str, size_t __len)
6898 { return basic_string<char>{__str, __len}; }
6899
6900#ifdef _GLIBCXX_USE_WCHAR_T1
6901 _GLIBCXX_DEFAULT_ABI_TAG__attribute ((__abi_tag__ ("cxx11")))
6902 inline basic_string<wchar_t>
6903 operator""s(const wchar_t* __str, size_t __len)
6904 { return basic_string<wchar_t>{__str, __len}; }
6905#endif
6906
6907#ifdef _GLIBCXX_USE_CHAR8_T
6908 _GLIBCXX_DEFAULT_ABI_TAG__attribute ((__abi_tag__ ("cxx11")))
6909 inline basic_string<char8_t>
6910 operator""s(const char8_t* __str, size_t __len)
6911 { return basic_string<char8_t>{__str, __len}; }
6912#endif
6913
6914 _GLIBCXX_DEFAULT_ABI_TAG__attribute ((__abi_tag__ ("cxx11")))
6915 inline basic_string<char16_t>
6916 operator""s(const char16_t* __str, size_t __len)
6917 { return basic_string<char16_t>{__str, __len}; }
6918
6919 _GLIBCXX_DEFAULT_ABI_TAG__attribute ((__abi_tag__ ("cxx11")))
6920 inline basic_string<char32_t>
6921 operator""s(const char32_t* __str, size_t __len)
6922 { return basic_string<char32_t>{__str, __len}; }
6923
6924#pragma GCC diagnostic pop
6925 } // inline namespace string_literals
6926 } // inline namespace literals
6927
6928#if __cplusplus201402L >= 201703L
6929 namespace __detail::__variant
6930 {
6931 template<typename> struct _Never_valueless_alt; // see <variant>
6932
6933 // Provide the strong exception-safety guarantee when emplacing a
6934 // basic_string into a variant, but only if moving the string cannot throw.
6935 template<typename _Tp, typename _Traits, typename _Alloc>
6936 struct _Never_valueless_alt<std::basic_string<_Tp, _Traits, _Alloc>>
6937 : __and_<
6938 is_nothrow_move_constructible<std::basic_string<_Tp, _Traits, _Alloc>>,
6939 is_nothrow_move_assignable<std::basic_string<_Tp, _Traits, _Alloc>>
6940 >::type
6941 { };
6942 } // namespace __detail::__variant
6943#endif // C++17
6944#endif // C++14
6945
6946_GLIBCXX_END_NAMESPACE_VERSION
6947} // namespace std
6948
6949#endif // C++11
6950
6951#endif /* _BASIC_STRING_H */
←

/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Bitstream/BitstreamReader.h

→
1//===- BitstreamReader.h - Low-level bitstream reader interface -*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This header defines the BitstreamReader class. This class can be used to
10// read an arbitrary bitstream, regardless of its contents.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_BITSTREAM_BITSTREAMREADER_H
15#define LLVM_BITSTREAM_BITSTREAMREADER_H
16
17#include "llvm/ADT/ArrayRef.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/Bitstream/BitCodes.h"
20#include "llvm/Support/Endian.h"
21#include "llvm/Support/Error.h"
22#include "llvm/Support/ErrorHandling.h"
23#include "llvm/Support/MathExtras.h"
24#include "llvm/Support/MemoryBuffer.h"
25#include <algorithm>
26#include <cassert>
27#include <climits>
28#include <cstddef>
29#include <cstdint>
30#include <memory>
31#include <string>
32#include <utility>
33#include <vector>
34
35namespace llvm {
36
37/// This class maintains the abbreviations read from a block info block.
38class BitstreamBlockInfo {
39public:
40 /// This contains information emitted to BLOCKINFO_BLOCK blocks. These
41 /// describe abbreviations that all blocks of the specified ID inherit.
42 struct BlockInfo {
43 unsigned BlockID = 0;
44 std::vector<std::shared_ptr<BitCodeAbbrev>> Abbrevs;
45 std::string Name;
46 std::vector<std::pair<unsigned, std::string>> RecordNames;
47 };
48
49private:
50 std::vector<BlockInfo> BlockInfoRecords;
51
52public:
53 /// If there is block info for the specified ID, return it, otherwise return
54 /// null.
55 const BlockInfo *getBlockInfo(unsigned BlockID) const {
56 // Common case, the most recent entry matches BlockID.
57 if (!BlockInfoRecords.empty() && BlockInfoRecords.back().BlockID == BlockID)
58 return &BlockInfoRecords.back();
59
60 for (unsigned i = 0, e = static_cast<unsigned>(BlockInfoRecords.size());
61 i != e; ++i)
62 if (BlockInfoRecords[i].BlockID == BlockID)
63 return &BlockInfoRecords[i];
64 return nullptr;
65 }
66
67 BlockInfo &getOrCreateBlockInfo(unsigned BlockID) {
68 if (const BlockInfo *BI = getBlockInfo(BlockID))
69 return *const_cast<BlockInfo*>(BI);
70
71 // Otherwise, add a new record.
72 BlockInfoRecords.emplace_back();
73 BlockInfoRecords.back().BlockID = BlockID;
74 return BlockInfoRecords.back();
75 }
76};
77
78/// This represents a position within a bitstream. There may be multiple
79/// independent cursors reading within one bitstream, each maintaining their
80/// own local state.
81class SimpleBitstreamCursor {
82 ArrayRef<uint8_t> BitcodeBytes;
83 size_t NextChar = 0;
84
85public:
86 /// This is the current data we have pulled from the stream but have not
87 /// returned to the client. This is specifically and intentionally defined to
88 /// follow the word size of the host machine for efficiency. We use word_t in
89 /// places that are aware of this to make it perfectly explicit what is going
90 /// on.
91 using word_t = size_t;
92
93private:
94 word_t CurWord = 0;
95
96 /// This is the number of bits in CurWord that are valid. This is always from
97 /// [0...bits_of(size_t)-1] inclusive.
98 unsigned BitsInCurWord = 0;
99
100public:
101 static const constexpr size_t MaxChunkSize = sizeof(word_t) * 8;
102
103 SimpleBitstreamCursor() = default;
104 explicit SimpleBitstreamCursor(ArrayRef<uint8_t> BitcodeBytes)
105 : BitcodeBytes(BitcodeBytes) {}
106 explicit SimpleBitstreamCursor(StringRef BitcodeBytes)
107 : BitcodeBytes(arrayRefFromStringRef(BitcodeBytes)) {}
108 explicit SimpleBitstreamCursor(MemoryBufferRef BitcodeBytes)
109 : SimpleBitstreamCursor(BitcodeBytes.getBuffer()) {}
110
111 bool canSkipToPos(size_t pos) const {
112 // pos can be skipped to if it is a valid address or one byte past the end.
113 return pos <= BitcodeBytes.size();
114 }
115
116 bool AtEndOfStream() {
117 return BitsInCurWord == 0 && BitcodeBytes.size() <= NextChar;
118 }
119
120 /// Return the bit # of the bit we are reading.
121 uint64_t GetCurrentBitNo() const {
122 return NextChar*CHAR_BIT8 - BitsInCurWord;
123 }
124
125 // Return the byte # of the current bit.
126 uint64_t getCurrentByteNo() const { return GetCurrentBitNo() / 8; }
127
128 ArrayRef<uint8_t> getBitcodeBytes() const { return BitcodeBytes; }
129
130 /// Reset the stream to the specified bit number.
131 Error JumpToBit(uint64_t BitNo) {
132 size_t ByteNo = size_t(BitNo/8) & ~(sizeof(word_t)-1);
133 unsigned WordBitNo = unsigned(BitNo & (sizeof(word_t)*8-1));
134 assert(canSkipToPos(ByteNo) && "Invalid location")(static_cast <bool> (canSkipToPos(ByteNo) && "Invalid location"
) ? void (0) : __assert_fail ("canSkipToPos(ByteNo) && \"Invalid location\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Bitstream/BitstreamReader.h"
, 134, __extension__ __PRETTY_FUNCTION__));
135
136 // Move the cursor to the right word.
137 NextChar = ByteNo;
138 BitsInCurWord = 0;
139
140 // Skip over any bits that are already consumed.
141 if (WordBitNo) {
142 if (Expected<word_t> Res = Read(WordBitNo))
143 return Error::success();
144 else
145 return Res.takeError();
146 }
147
148 return Error::success();
149 }
150
151 /// Get a pointer into the bitstream at the specified byte offset.
152 const uint8_t *getPointerToByte(uint64_t ByteNo, uint64_t NumBytes) {
153 return BitcodeBytes.data() + ByteNo;
154 }
155
156 /// Get a pointer into the bitstream at the specified bit offset.
157 ///
158 /// The bit offset must be on a byte boundary.
159 const uint8_t *getPointerToBit(uint64_t BitNo, uint64_t NumBytes) {
160 assert(!(BitNo % 8) && "Expected bit on byte boundary")(static_cast <bool> (!(BitNo % 8) && "Expected bit on byte boundary"
) ? void (0) : __assert_fail ("!(BitNo % 8) && \"Expected bit on byte boundary\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Bitstream/BitstreamReader.h"
, 160, __extension__ __PRETTY_FUNCTION__));
161 return getPointerToByte(BitNo / 8, NumBytes);
162 }
163
164 Error fillCurWord() {
165 if (NextChar >= BitcodeBytes.size())
166 return createStringError(std::errc::io_error,
167 "Unexpected end of file reading %u of %u bytes",
168 NextChar, BitcodeBytes.size());
169
170 // Read the next word from the stream.
171 const uint8_t *NextCharPtr = BitcodeBytes.data() + NextChar;
172 unsigned BytesRead;
173 if (BitcodeBytes.size() >= NextChar + sizeof(word_t)) {
174 BytesRead = sizeof(word_t);
175 CurWord =
176 support::endian::read<word_t, support::little, support::unaligned>(
177 NextCharPtr);
178 } else {
179 // Short read.
180 BytesRead = BitcodeBytes.size() - NextChar;
181 CurWord = 0;
182 for (unsigned B = 0; B != BytesRead; ++B)
183 CurWord |= uint64_t(NextCharPtr[B]) << (B * 8);
184 }
185 NextChar += BytesRead;
186 BitsInCurWord = BytesRead * 8;
187 return Error::success();
188 }
189
190 Expected<word_t> Read(unsigned NumBits) {
191 static const unsigned BitsInWord = MaxChunkSize;
192
193 assert(NumBits && NumBits <= BitsInWord &&(static_cast <bool> (NumBits && NumBits <= BitsInWord
&& "Cannot return zero or more than BitsInWord bits!"
) ? void (0) : __assert_fail ("NumBits && NumBits <= BitsInWord && \"Cannot return zero or more than BitsInWord bits!\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Bitstream/BitstreamReader.h"
, 194, __extension__ __PRETTY_FUNCTION__))
14
←
Assuming 'NumBits' is not equal to 0
→
15
←
Assuming 'NumBits' is <= 'BitsInWord'
→
16
←
'?' condition is true
→
194 "Cannot return zero or more than BitsInWord bits!")(static_cast <bool> (NumBits && NumBits <= BitsInWord
&& "Cannot return zero or more than BitsInWord bits!"
) ? void (0) : __assert_fail ("NumBits && NumBits <= BitsInWord && \"Cannot return zero or more than BitsInWord bits!\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Bitstream/BitstreamReader.h"
, 194, __extension__ __PRETTY_FUNCTION__));
195
196 static const unsigned Mask = sizeof(word_t) > 4 ? 0x3f : 0x1f;
17
←
'?' condition is true
→
197
198 // If the field is fully contained by CurWord, return it quickly.
199 if (BitsInCurWord >= NumBits) {
18
←
Assuming 'NumBits' is > field 'BitsInCurWord'
→
200 word_t R = CurWord & (~word_t(0) >> (BitsInWord - NumBits));
201
202 // Use a mask to avoid undefined behavior.
203 CurWord >>= (NumBits & Mask);
204
205 BitsInCurWord -= NumBits;
206 return R;
207 }
208
209 word_t R = BitsInCurWord
19.1
Field 'BitsInCurWord' is not equal to 0
19.1
Field 'BitsInCurWord' is not equal to 0
19.1
Field 'BitsInCurWord' is not equal to 0
19.1
Field 'BitsInCurWord' is not equal to 0
 ? CurWord : 0;
19
←
Taking false branch
→
20
←
'?' condition is true
→
210 unsigned BitsLeft = NumBits - BitsInCurWord;
211
212 if (Error fillResult = fillCurWord())
21
←
Calling 'Error::operator bool'
→
23
←
Returning from 'Error::operator bool'
→
24
←
Taking false branch
→
213 return std::move(fillResult);
214
215 // If we run out of data, abort.
216 if (BitsLeft > BitsInCurWord)
25
←
Assuming 'BitsLeft' is <= field 'BitsInCurWord'
→
26
←
Taking false branch
→
217 return createStringError(std::errc::io_error,
218 "Unexpected end of file reading %u of %u bits",
219 BitsInCurWord, BitsLeft);
220
221 word_t R2 = CurWord & (~word_t(0) >> (BitsInWord - BitsLeft));
27
←
The result of the right shift is undefined due to shifting by '64', which is greater or equal to the width of type 'llvm::SimpleBitstreamCursor::word_t'
222
223 // Use a mask to avoid undefined behavior.
224 CurWord >>= (BitsLeft & Mask);
225
226 BitsInCurWord -= BitsLeft;
227
228 R |= R2 << (NumBits - BitsLeft);
229
230 return R;
231 }
232
233 Expected<uint32_t> ReadVBR(unsigned NumBits) {
234 Expected<unsigned> MaybeRead = Read(NumBits);
235 if (!MaybeRead)
236 return MaybeRead;
237 uint32_t Piece = MaybeRead.get();
238
239 if ((Piece & (1U << (NumBits-1))) == 0)
240 return Piece;
241
242 uint32_t Result = 0;
243 unsigned NextBit = 0;
244 while (true) {
245 Result |= (Piece & ((1U << (NumBits-1))-1)) << NextBit;
246
247 if ((Piece & (1U << (NumBits-1))) == 0)
248 return Result;
249
250 NextBit += NumBits-1;
251 MaybeRead = Read(NumBits);
252 if (!MaybeRead)
253 return MaybeRead;
254 Piece = MaybeRead.get();
255 }
256 }
257
258 // Read a VBR that may have a value up to 64-bits in size. The chunk size of
259 // the VBR must still be <= 32 bits though.
260 Expected<uint64_t> ReadVBR64(unsigned NumBits) {
261 Expected<uint64_t> MaybeRead = Read(NumBits);
262 if (!MaybeRead)
263 return MaybeRead;
264 uint32_t Piece = MaybeRead.get();
265
266 if ((Piece & (1U << (NumBits-1))) == 0)
267 return uint64_t(Piece);
268
269 uint64_t Result = 0;
270 unsigned NextBit = 0;
271 while (true) {
272 Result |= uint64_t(Piece & ((1U << (NumBits-1))-1)) << NextBit;
273
274 if ((Piece & (1U << (NumBits-1))) == 0)
275 return Result;
276
277 NextBit += NumBits-1;
278 MaybeRead = Read(NumBits);
279 if (!MaybeRead)
280 return MaybeRead;
281 Piece = MaybeRead.get();
282 }
283 }
284
285 void SkipToFourByteBoundary() {
286 // If word_t is 64-bits and if we've read less than 32 bits, just dump
287 // the bits we have up to the next 32-bit boundary.
288 if (sizeof(word_t) > 4 &&
289 BitsInCurWord >= 32) {
290 CurWord >>= BitsInCurWord-32;
291 BitsInCurWord = 32;
292 return;
293 }
294
295 BitsInCurWord = 0;
296 }
297
298 /// Return the size of the stream in bytes.
299 size_t SizeInBytes() const { return BitcodeBytes.size(); }
300
301 /// Skip to the end of the file.
302 void skipToEnd() { NextChar = BitcodeBytes.size(); }
303};
304
305/// When advancing through a bitstream cursor, each advance can discover a few
306/// different kinds of entries:
307struct BitstreamEntry {
308 enum {
309 Error, // Malformed bitcode was found.
310 EndBlock, // We've reached the end of the current block, (or the end of the
311 // file, which is treated like a series of EndBlock records.
312 SubBlock, // This is the start of a new subblock of a specific ID.
313 Record // This is a record with a specific AbbrevID.
314 } Kind;
315
316 unsigned ID;
317
318 static BitstreamEntry getError() {
319 BitstreamEntry E; E.Kind = Error; return E;
320 }
321
322 static BitstreamEntry getEndBlock() {
323 BitstreamEntry E; E.Kind = EndBlock; return E;
324 }
325
326 static BitstreamEntry getSubBlock(unsigned ID) {
327 BitstreamEntry E; E.Kind = SubBlock; E.ID = ID; return E;
328 }
329
330 static BitstreamEntry getRecord(unsigned AbbrevID) {
331 BitstreamEntry E; E.Kind = Record; E.ID = AbbrevID; return E;
332 }
333};
334
335/// This represents a position within a bitcode file, implemented on top of a
336/// SimpleBitstreamCursor.
337///
338/// Unlike iterators, BitstreamCursors are heavy-weight objects that should not
339/// be passed by value.
340class BitstreamCursor : SimpleBitstreamCursor {
341 // This is the declared size of code values used for the current block, in
342 // bits.
343 unsigned CurCodeSize = 2;
344
345 /// Abbrevs installed at in this block.
346 std::vector<std::shared_ptr<BitCodeAbbrev>> CurAbbrevs;
347
348 struct Block {
349 unsigned PrevCodeSize;
350 std::vector<std::shared_ptr<BitCodeAbbrev>> PrevAbbrevs;
351
352 explicit Block(unsigned PCS) : PrevCodeSize(PCS) {}
353 };
354
355 /// This tracks the codesize of parent blocks.
356 SmallVector<Block, 8> BlockScope;
357
358 BitstreamBlockInfo *BlockInfo = nullptr;
359
360public:
361 static const size_t MaxChunkSize = sizeof(word_t) * 8;
362
363 BitstreamCursor() = default;
364 explicit BitstreamCursor(ArrayRef<uint8_t> BitcodeBytes)
365 : SimpleBitstreamCursor(BitcodeBytes) {}
366 explicit BitstreamCursor(StringRef BitcodeBytes)
367 : SimpleBitstreamCursor(BitcodeBytes) {}
368 explicit BitstreamCursor(MemoryBufferRef BitcodeBytes)
369 : SimpleBitstreamCursor(BitcodeBytes) {}
370
371 using SimpleBitstreamCursor::AtEndOfStream;
372 using SimpleBitstreamCursor::canSkipToPos;
373 using SimpleBitstreamCursor::fillCurWord;
374 using SimpleBitstreamCursor::getBitcodeBytes;
375 using SimpleBitstreamCursor::GetCurrentBitNo;
376 using SimpleBitstreamCursor::getCurrentByteNo;
377 using SimpleBitstreamCursor::getPointerToByte;
378 using SimpleBitstreamCursor::JumpToBit;
379 using SimpleBitstreamCursor::Read;
380 using SimpleBitstreamCursor::ReadVBR;
381 using SimpleBitstreamCursor::ReadVBR64;
382 using SimpleBitstreamCursor::SizeInBytes;
383 using SimpleBitstreamCursor::skipToEnd;
384
385 /// Return the number of bits used to encode an abbrev #.
386 unsigned getAbbrevIDWidth() const { return CurCodeSize; }
387
388 /// Flags that modify the behavior of advance().
389 enum {
390 /// If this flag is used, the advance() method does not automatically pop
391 /// the block scope when the end of a block is reached.
392 AF_DontPopBlockAtEnd = 1,
393
394 /// If this flag is used, abbrev entries are returned just like normal
395 /// records.
396 AF_DontAutoprocessAbbrevs = 2
397 };
398
399 /// Advance the current bitstream, returning the next entry in the stream.
400 Expected<BitstreamEntry> advance(unsigned Flags = 0) {
401 while (true) {
10
←
Loop condition is true. Entering loop body
→
402 if (AtEndOfStream())
11
←
Taking false branch
→
403 return BitstreamEntry::getError();
404
405 Expected<unsigned> MaybeCode = ReadCode();
12
←
Calling 'BitstreamCursor::ReadCode'
→
406 if (!MaybeCode)
407 return MaybeCode.takeError();
408 unsigned Code = MaybeCode.get();
409
410 if (Code == bitc::END_BLOCK) {
411 // Pop the end of the block unless Flags tells us not to.
412 if (!(Flags & AF_DontPopBlockAtEnd) && ReadBlockEnd())
413 return BitstreamEntry::getError();
414 return BitstreamEntry::getEndBlock();
415 }
416
417 if (Code == bitc::ENTER_SUBBLOCK) {
418 if (Expected<unsigned> MaybeSubBlock = ReadSubBlockID())
419 return BitstreamEntry::getSubBlock(MaybeSubBlock.get());
420 else
421 return MaybeSubBlock.takeError();
422 }
423
424 if (Code == bitc::DEFINE_ABBREV &&
425 !(Flags & AF_DontAutoprocessAbbrevs)) {
426 // We read and accumulate abbrev's, the client can't do anything with
427 // them anyway.
428 if (Error Err = ReadAbbrevRecord())
429 return std::move(Err);
430 continue;
431 }
432
433 return BitstreamEntry::getRecord(Code);
434 }
435 }
436
437 /// This is a convenience function for clients that don't expect any
438 /// subblocks. This just skips over them automatically.
439 Expected<BitstreamEntry> advanceSkippingSubblocks(unsigned Flags = 0) {
440 while (true) {
441 // If we found a normal entry, return it.
442 Expected<BitstreamEntry> MaybeEntry = advance(Flags);
443 if (!MaybeEntry)
444 return MaybeEntry;
445 BitstreamEntry Entry = MaybeEntry.get();
446
447 if (Entry.Kind != BitstreamEntry::SubBlock)
448 return Entry;
449
450 // If we found a sub-block, just skip over it and check the next entry.
451 if (Error Err = SkipBlock())
452 return std::move(Err);
453 }
454 }
455
456 Expected<unsigned> ReadCode() { return Read(CurCodeSize); }
13
←
Calling 'SimpleBitstreamCursor::Read'
→
457
458 // Block header:
459 // [ENTER_SUBBLOCK, blockid, newcodelen, <align4bytes>, blocklen]
460
461 /// Having read the ENTER_SUBBLOCK code, read the BlockID for the block.
462 Expected<unsigned> ReadSubBlockID() { return ReadVBR(bitc::BlockIDWidth); }
463
464 /// Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip over the body
465 /// of this block.
466 Error SkipBlock() {
467 // Read and ignore the codelen value.
468 if (Expected<uint32_t> Res = ReadVBR(bitc::CodeLenWidth))
469 ; // Since we are skipping this block, we don't care what code widths are
470 // used inside of it.
471 else
472 return Res.takeError();
473
474 SkipToFourByteBoundary();
475 Expected<unsigned> MaybeNum = Read(bitc::BlockSizeWidth);
476 if (!MaybeNum)
477 return MaybeNum.takeError();
478 size_t NumFourBytes = MaybeNum.get();
479
480 // Check that the block wasn't partially defined, and that the offset isn't
481 // bogus.
482 size_t SkipTo = GetCurrentBitNo() + NumFourBytes * 4 * 8;
483 if (AtEndOfStream())
484 return createStringError(std::errc::illegal_byte_sequence,
485 "can't skip block: already at end of stream");
486 if (!canSkipToPos(SkipTo / 8))
487 return createStringError(std::errc::illegal_byte_sequence,
488 "can't skip to bit %zu from %" PRIu64"l" "u", SkipTo,
489 GetCurrentBitNo());
490
491 if (Error Res = JumpToBit(SkipTo))
492 return Res;
493
494 return Error::success();
495 }
496
497 /// Having read the ENTER_SUBBLOCK abbrevid, and enter the block.
498 Error EnterSubBlock(unsigned BlockID, unsigned *NumWordsP = nullptr);
499
500 bool ReadBlockEnd() {
501 if (BlockScope.empty()) return true;
502
503 // Block tail:
504 // [END_BLOCK, <align4bytes>]
505 SkipToFourByteBoundary();
506
507 popBlockScope();
508 return false;
509 }
510
511private:
512 void popBlockScope() {
513 CurCodeSize = BlockScope.back().PrevCodeSize;
514
515 CurAbbrevs = std::move(BlockScope.back().PrevAbbrevs);
516 BlockScope.pop_back();
517 }
518
519 //===--------------------------------------------------------------------===//
520 // Record Processing
521 //===--------------------------------------------------------------------===//
522
523public:
524 /// Return the abbreviation for the specified AbbrevId.
525 const BitCodeAbbrev *getAbbrev(unsigned AbbrevID) {
526 unsigned AbbrevNo = AbbrevID - bitc::FIRST_APPLICATION_ABBREV;
527 if (AbbrevNo >= CurAbbrevs.size())
528 report_fatal_error("Invalid abbrev number");
529 return CurAbbrevs[AbbrevNo].get();
530 }
531
532 /// Read the current record and discard it, returning the code for the record.
533 Expected<unsigned> skipRecord(unsigned AbbrevID);
534
535 Expected<unsigned> readRecord(unsigned AbbrevID,
536 SmallVectorImpl<uint64_t> &Vals,
537 StringRef *Blob = nullptr);
538
539 //===--------------------------------------------------------------------===//
540 // Abbrev Processing
541 //===--------------------------------------------------------------------===//
542 Error ReadAbbrevRecord();
543
544 /// Read and return a block info block from the bitstream. If an error was
545 /// encountered, return None.
546 ///
547 /// \param ReadBlockInfoNames Whether to read block/record name information in
548 /// the BlockInfo block. Only llvm-bcanalyzer uses this.
549 Expected<Optional<BitstreamBlockInfo>>
550 ReadBlockInfoBlock(bool ReadBlockInfoNames = false);
551
552 /// Set the block info to be used by this BitstreamCursor to interpret
553 /// abbreviated records.
554 void setBlockInfo(BitstreamBlockInfo *BI) { BlockInfo = BI; }
555};
556
557} // end llvm namespace
558
559#endif // LLVM_BITSTREAM_BITSTREAMREADER_H
←

/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines an API used to report recoverable errors.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_SUPPORT_ERROR_H
14#define LLVM_SUPPORT_ERROR_H
15
16#include "llvm-c/Error.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/ADT/StringExtras.h"
20#include "llvm/ADT/Twine.h"
21#include "llvm/Config/abi-breaking.h"
22#include "llvm/Support/AlignOf.h"
23#include "llvm/Support/Compiler.h"
24#include "llvm/Support/Debug.h"
25#include "llvm/Support/ErrorHandling.h"
26#include "llvm/Support/ErrorOr.h"
27#include "llvm/Support/Format.h"
28#include "llvm/Support/raw_ostream.h"
29#include <algorithm>
30#include <cassert>
31#include <cstdint>
32#include <cstdlib>
33#include <functional>
34#include <memory>
35#include <new>
36#include <string>
37#include <system_error>
38#include <type_traits>
39#include <utility>
40#include <vector>
41
42namespace llvm {
43
44class ErrorSuccess;
45
46/// Base class for error info classes. Do not extend this directly: Extend
47/// the ErrorInfo template subclass instead.
48class ErrorInfoBase {
49public:
50 virtual ~ErrorInfoBase() = default;
51
52 /// Print an error message to an output stream.
53 virtual void log(raw_ostream &OS) const = 0;
54
55 /// Return the error message as a string.
56 virtual std::string message() const {
57 std::string Msg;
58 raw_string_ostream OS(Msg);
59 log(OS);
60 return OS.str();
61 }
62
63 /// Convert this error to a std::error_code.
64 ///
65 /// This is a temporary crutch to enable interaction with code still
66 /// using std::error_code. It will be removed in the future.
67 virtual std::error_code convertToErrorCode() const = 0;
68
69 // Returns the class ID for this type.
70 static const void *classID() { return &ID; }
71
72 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
73 virtual const void *dynamicClassID() const = 0;
74
75 // Check whether this instance is a subclass of the class identified by
76 // ClassID.
77 virtual bool isA(const void *const ClassID) const {
78 return ClassID == classID();
79 }
80
81 // Check whether this instance is a subclass of ErrorInfoT.
82 template <typename ErrorInfoT> bool isA() const {
83 return isA(ErrorInfoT::classID());
84 }
85
86private:
87 virtual void anchor();
88
89 static char ID;
90};
91
92/// Lightweight error class with error context and mandatory checking.
93///
94/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
95/// are represented by setting the pointer to a ErrorInfoBase subclass
96/// instance containing information describing the failure. Success is
97/// represented by a null pointer value.
98///
99/// Instances of Error also contains a 'Checked' flag, which must be set
100/// before the destructor is called, otherwise the destructor will trigger a
101/// runtime error. This enforces at runtime the requirement that all Error
102/// instances be checked or returned to the caller.
103///
104/// There are two ways to set the checked flag, depending on what state the
105/// Error instance is in. For Error instances indicating success, it
106/// is sufficient to invoke the boolean conversion operator. E.g.:
107///
108/// @code{.cpp}
109/// Error foo(<...>);
110///
111/// if (auto E = foo(<...>))
112/// return E; // <- Return E if it is in the error state.
113/// // We have verified that E was in the success state. It can now be safely
114/// // destroyed.
115/// @endcode
116///
117/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
118/// without testing the return value will raise a runtime error, even if foo
119/// returns success.
120///
121/// For Error instances representing failure, you must use either the
122/// handleErrors or handleAllErrors function with a typed handler. E.g.:
123///
124/// @code{.cpp}
125/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
126/// // Custom error info.
127/// };
128///
129/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
130///
131/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
132/// auto NewE =
133/// handleErrors(E,
134/// [](const MyErrorInfo &M) {
135/// // Deal with the error.
136/// },
137/// [](std::unique_ptr<OtherError> M) -> Error {
138/// if (canHandle(*M)) {
139/// // handle error.
140/// return Error::success();
141/// }
142/// // Couldn't handle this error instance. Pass it up the stack.
143/// return Error(std::move(M));
144/// );
145/// // Note - we must check or return NewE in case any of the handlers
146/// // returned a new error.
147/// @endcode
148///
149/// The handleAllErrors function is identical to handleErrors, except
150/// that it has a void return type, and requires all errors to be handled and
151/// no new errors be returned. It prevents errors (assuming they can all be
152/// handled) from having to be bubbled all the way to the top-level.
153///
154/// *All* Error instances must be checked before destruction, even if
155/// they're moved-assigned or constructed from Success values that have already
156/// been checked. This enforces checking through all levels of the call stack.
157class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
158 // ErrorList needs to be able to yank ErrorInfoBase pointers out of Errors
159 // to add to the error list. It can't rely on handleErrors for this, since
160 // handleErrors does not support ErrorList handlers.
161 friend class ErrorList;
162
163 // handleErrors needs to be able to set the Checked flag.
164 template <typename... HandlerTs>
165 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
166
167 // Expected<T> needs to be able to steal the payload when constructed from an
168 // error.
169 template <typename T> friend class Expected;
170
171 // wrap needs to be able to steal the payload.
172 friend LLVMErrorRef wrap(Error);
173
174protected:
175 /// Create a success value. Prefer using 'Error::success()' for readability
176 Error() {
177 setPtr(nullptr);
178 setChecked(false);
179 }
180
181public:
182 /// Create a success value.
183 static ErrorSuccess success();
184
185 // Errors are not copy-constructable.
186 Error(const Error &Other) = delete;
187
188 /// Move-construct an error value. The newly constructed error is considered
189 /// unchecked, even if the source error had been checked. The original error
190 /// becomes a checked Success value, regardless of its original state.
191 Error(Error &&Other) {
192 setChecked(true);
193 *this = std::move(Other);
194 }
195
196 /// Create an error value. Prefer using the 'make_error' function, but
197 /// this constructor can be useful when "re-throwing" errors from handlers.
198 Error(std::unique_ptr<ErrorInfoBase> Payload) {
199 setPtr(Payload.release());
200 setChecked(false);
201 }
202
203 // Errors are not copy-assignable.
204 Error &operator=(const Error &Other) = delete;
205
206 /// Move-assign an error value. The current error must represent success, you
207 /// you cannot overwrite an unhandled error. The current error is then
208 /// considered unchecked. The source error becomes a checked success value,
209 /// regardless of its original state.
210 Error &operator=(Error &&Other) {
211 // Don't allow overwriting of unchecked values.
212 assertIsChecked();
213 setPtr(Other.getPtr());
214
215 // This Error is unchecked, even if the source error was checked.
216 setChecked(false);
217
218 // Null out Other's payload and set its checked bit.
219 Other.setPtr(nullptr);
220 Other.setChecked(true);
221
222 return *this;
223 }
224
225 /// Destroy a Error. Fails with a call to abort() if the error is
226 /// unchecked.
227 ~Error() {
228 assertIsChecked();
229 delete getPtr();
230 }
231
232 /// Bool conversion. Returns true if this Error is in a failure state,
233 /// and false if it is in an accept state. If the error is in a Success state
234 /// it will be considered checked.
235 explicit operator bool() {
236 setChecked(getPtr() == nullptr);
237 return getPtr() != nullptr;
22
←
Returning zero, which participates in a condition later
→
238 }
239
240 /// Check whether one error is a subclass of another.
241 template <typename ErrT> bool isA() const {
242 return getPtr() && getPtr()->isA(ErrT::classID());
243 }
244
245 /// Returns the dynamic class id of this error, or null if this is a success
246 /// value.
247 const void* dynamicClassID() const {
248 if (!getPtr())
249 return nullptr;
250 return getPtr()->dynamicClassID();
251 }
252
253private:
254#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
255 // assertIsChecked() happens very frequently, but under normal circumstances
256 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
257 // of debug prints can cause the function to be too large for inlining. So
258 // it's important that we define this function out of line so that it can't be
259 // inlined.
260 [[noreturn]] void fatalUncheckedError() const;
261#endif
262
263 void assertIsChecked() {
264#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
265 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
266 fatalUncheckedError();
267#endif
268 }
269
270 ErrorInfoBase *getPtr() const {
271#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
272 return reinterpret_cast<ErrorInfoBase*>(
273 reinterpret_cast<uintptr_t>(Payload) &
274 ~static_cast<uintptr_t>(0x1));
275#else
276 return Payload;
277#endif
278 }
279
280 void setPtr(ErrorInfoBase *EI) {
281#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
282 Payload = reinterpret_cast<ErrorInfoBase*>(
283 (reinterpret_cast<uintptr_t>(EI) &
284 ~static_cast<uintptr_t>(0x1)) |
285 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
286#else
287 Payload = EI;
288#endif
289 }
290
291 bool getChecked() const {
292#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
293 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
294#else
295 return true;
296#endif
297 }
298
299 void setChecked(bool V) {
300#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
301 Payload = reinterpret_cast<ErrorInfoBase*>(
302 (reinterpret_cast<uintptr_t>(Payload) &
303 ~static_cast<uintptr_t>(0x1)) |
304 (V ? 0 : 1));
305#endif
306 }
307
308 std::unique_ptr<ErrorInfoBase> takePayload() {
309 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
310 setPtr(nullptr);
311 setChecked(true);
312 return Tmp;
313 }
314
315 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
316 if (auto P = E.getPtr())
317 P->log(OS);
318 else
319 OS << "success";
320 return OS;
321 }
322
323 ErrorInfoBase *Payload = nullptr;
324};
325
326/// Subclass of Error for the sole purpose of identifying the success path in
327/// the type system. This allows to catch invalid conversion to Expected<T> at
328/// compile time.
329class ErrorSuccess final : public Error {};
330
331inline ErrorSuccess Error::success() { return ErrorSuccess(); }
332
333/// Make a Error instance representing failure using the given error info
334/// type.
335template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
336 return Error(std::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
337}
338
339/// Base class for user error types. Users should declare their error types
340/// like:
341///
342/// class MyError : public ErrorInfo<MyError> {
343/// ....
344/// };
345///
346/// This class provides an implementation of the ErrorInfoBase::kind
347/// method, which is used by the Error RTTI system.
348template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
349class ErrorInfo : public ParentErrT {
350public:
351 using ParentErrT::ParentErrT; // inherit constructors
352
353 static const void *classID() { return &ThisErrT::ID; }
354
355 const void *dynamicClassID() const override { return &ThisErrT::ID; }
356
357 bool isA(const void *const ClassID) const override {
358 return ClassID == classID() || ParentErrT::isA(ClassID);
359 }
360};
361
362/// Special ErrorInfo subclass representing a list of ErrorInfos.
363/// Instances of this class are constructed by joinError.
364class ErrorList final : public ErrorInfo<ErrorList> {
365 // handleErrors needs to be able to iterate the payload list of an
366 // ErrorList.
367 template <typename... HandlerTs>
368 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
369
370 // joinErrors is implemented in terms of join.
371 friend Error joinErrors(Error, Error);
372
373public:
374 void log(raw_ostream &OS) const override {
375 OS << "Multiple errors:\n";
376 for (auto &ErrPayload : Payloads) {
377 ErrPayload->log(OS);
378 OS << "\n";
379 }
380 }
381
382 std::error_code convertToErrorCode() const override;
383
384 // Used by ErrorInfo::classID.
385 static char ID;
386
387private:
388 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
389 std::unique_ptr<ErrorInfoBase> Payload2) {
390 assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
"ErrorList constructor payloads should be singleton errors")
? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 391, __extension__ __PRETTY_FUNCTION__))
391 "ErrorList constructor payloads should be singleton errors")(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
"ErrorList constructor payloads should be singleton errors")
? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 391, __extension__ __PRETTY_FUNCTION__));
392 Payloads.push_back(std::move(Payload1));
393 Payloads.push_back(std::move(Payload2));
394 }
395
396 static Error join(Error E1, Error E2) {
397 if (!E1)
398 return E2;
399 if (!E2)
400 return E1;
401 if (E1.isA<ErrorList>()) {
402 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
403 if (E2.isA<ErrorList>()) {
404 auto E2Payload = E2.takePayload();
405 auto &E2List = static_cast<ErrorList &>(*E2Payload);
406 for (auto &Payload : E2List.Payloads)
407 E1List.Payloads.push_back(std::move(Payload));
408 } else
409 E1List.Payloads.push_back(E2.takePayload());
410
411 return E1;
412 }
413 if (E2.isA<ErrorList>()) {
414 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
415 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
416 return E2;
417 }
418 return Error(std::unique_ptr<ErrorList>(
419 new ErrorList(E1.takePayload(), E2.takePayload())));
420 }
421
422 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
423};
424
425/// Concatenate errors. The resulting Error is unchecked, and contains the
426/// ErrorInfo(s), if any, contained in E1, followed by the
427/// ErrorInfo(s), if any, contained in E2.
428inline Error joinErrors(Error E1, Error E2) {
429 return ErrorList::join(std::move(E1), std::move(E2));
430}
431
432/// Tagged union holding either a T or a Error.
433///
434/// This class parallels ErrorOr, but replaces error_code with Error. Since
435/// Error cannot be copied, this class replaces getError() with
436/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
437/// error class type.
438///
439/// Example usage of 'Expected<T>' as a function return type:
440///
441/// @code{.cpp}
442/// Expected<int> myDivide(int A, int B) {
443/// if (B == 0) {
444/// // return an Error
445/// return createStringError(inconvertibleErrorCode(),
446/// "B must not be zero!");
447/// }
448/// // return an integer
449/// return A / B;
450/// }
451/// @endcode
452///
453/// Checking the results of to a function returning 'Expected<T>':
454/// @code{.cpp}
455/// if (auto E = Result.takeError()) {
456/// // We must consume the error. Typically one of:
457/// // - return the error to our caller
458/// // - toString(), when logging
459/// // - consumeError(), to silently swallow the error
460/// // - handleErrors(), to distinguish error types
461/// errs() << "Problem with division " << toString(std::move(E)) << "\n";
462/// return;
463/// }
464/// // use the result
465/// outs() << "The answer is " << *Result << "\n";
466/// @endcode
467///
468/// For unit-testing a function returning an 'Expceted<T>', see the
469/// 'EXPECT_THAT_EXPECTED' macros in llvm/Testing/Support/Error.h
470
471template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
472 template <class T1> friend class ExpectedAsOutParameter;
473 template <class OtherT> friend class Expected;
474
475 static constexpr bool isRef = std::is_reference<T>::value;
476
477 using wrap = std::reference_wrapper<std::remove_reference_t<T>>;
478
479 using error_type = std::unique_ptr<ErrorInfoBase>;
480
481public:
482 using storage_type = std::conditional_t<isRef, wrap, T>;
483 using value_type = T;
484
485private:
486 using reference = std::remove_reference_t<T> &;
487 using const_reference = const std::remove_reference_t<T> &;
488 using pointer = std::remove_reference_t<T> *;
489 using const_pointer = const std::remove_reference_t<T> *;
490
491public:
492 /// Create an Expected<T> error value from the given Error.
493 Expected(Error Err)
494 : HasError(true)
495#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
496 // Expected is unchecked upon construction in Debug builds.
497 , Unchecked(true)
498#endif
499 {
500 assert(Err && "Cannot create Expected<T> from Error success value.")(static_cast <bool> (Err && "Cannot create Expected<T> from Error success value."
) ? void (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 500, __extension__ __PRETTY_FUNCTION__));
501 new (getErrorStorage()) error_type(Err.takePayload());
502 }
503
504 /// Forbid to convert from Error::success() implicitly, this avoids having
505 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
506 /// but triggers the assertion above.
507 Expected(ErrorSuccess) = delete;
508
509 /// Create an Expected<T> success value from the given OtherT value, which
510 /// must be convertible to T.
511 template <typename OtherT>
512 Expected(OtherT &&Val,
513 std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr)
514 : HasError(false)
515#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
516 // Expected is unchecked upon construction in Debug builds.
517 ,
518 Unchecked(true)
519#endif
520 {
521 new (getStorage()) storage_type(std::forward<OtherT>(Val));
522 }
523
524 /// Move construct an Expected<T> value.
525 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
526
527 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
528 /// must be convertible to T.
529 template <class OtherT>
530 Expected(
531 Expected<OtherT> &&Other,
532 std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr) {
533 moveConstruct(std::move(Other));
534 }
535
536 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
537 /// isn't convertible to T.
538 template <class OtherT>
539 explicit Expected(
540 Expected<OtherT> &&Other,
541 std::enable_if_t<!std::is_convertible<OtherT, T>::value> * = nullptr) {
542 moveConstruct(std::move(Other));
543 }
544
545 /// Move-assign from another Expected<T>.
546 Expected &operator=(Expected &&Other) {
547 moveAssign(std::move(Other));
548 return *this;
549 }
550
551 /// Destroy an Expected<T>.
552 ~Expected() {
553 assertIsChecked();
554 if (!HasError)
555 getStorage()->~storage_type();
556 else
557 getErrorStorage()->~error_type();
558 }
559
560 /// Return false if there is an error.
561 explicit operator bool() {
562#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
563 Unchecked = HasError;
564#endif
565 return !HasError;
566 }
567
568 /// Returns a reference to the stored T value.
569 reference get() {
570 assertIsChecked();
571 return *getStorage();
572 }
573
574 /// Returns a const reference to the stored T value.
575 const_reference get() const {
576 assertIsChecked();
577 return const_cast<Expected<T> *>(this)->get();
578 }
579
580 /// Check that this Expected<T> is an error of type ErrT.
581 template <typename ErrT> bool errorIsA() const {
582 return HasError && (*getErrorStorage())->template isA<ErrT>();
583 }
584
585 /// Take ownership of the stored error.
586 /// After calling this the Expected<T> is in an indeterminate state that can
587 /// only be safely destructed. No further calls (beside the destructor) should
588 /// be made on the Expected<T> value.
589 Error takeError() {
590#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
591 Unchecked = false;
592#endif
593 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
594 }
595
596 /// Returns a pointer to the stored T value.
597 pointer operator->() {
598 assertIsChecked();
599 return toPointer(getStorage());
600 }
601
602 /// Returns a const pointer to the stored T value.
603 const_pointer operator->() const {
604 assertIsChecked();
605 return toPointer(getStorage());
606 }
607
608 /// Returns a reference to the stored T value.
609 reference operator*() {
610 assertIsChecked();
611 return *getStorage();
612 }
613
614 /// Returns a const reference to the stored T value.
615 const_reference operator*() const {
616 assertIsChecked();
617 return *getStorage();
618 }
619
620private:
621 template <class T1>
622 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
623 return &a == &b;
624 }
625
626 template <class T1, class T2>
627 static bool compareThisIfSameType(const T1 &, const T2 &) {
628 return false;
629 }
630
631 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
632 HasError = Other.HasError;
633#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
634 Unchecked = true;
635 Other.Unchecked = false;
636#endif
637
638 if (!HasError)
639 new (getStorage()) storage_type(std::move(*Other.getStorage()));
640 else
641 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
642 }
643
644 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
645 assertIsChecked();
646
647 if (compareThisIfSameType(*this, Other))
648 return;
649
650 this->~Expected();
651 new (this) Expected(std::move(Other));
652 }
653
654 pointer toPointer(pointer Val) { return Val; }
655
656 const_pointer toPointer(const_pointer Val) const { return Val; }
657
658 pointer toPointer(wrap *Val) { return &Val->get(); }
659
660 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
661
662 storage_type *getStorage() {
663 assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 663, __extension__ __PRETTY_FUNCTION__));
664 return reinterpret_cast<storage_type *>(&TStorage);
665 }
666
667 const storage_type *getStorage() const {
668 assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 668, __extension__ __PRETTY_FUNCTION__));
669 return reinterpret_cast<const storage_type *>(&TStorage);
670 }
671
672 error_type *getErrorStorage() {
673 assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 673, __extension__ __PRETTY_FUNCTION__));
674 return reinterpret_cast<error_type *>(&ErrorStorage);
675 }
676
677 const error_type *getErrorStorage() const {
678 assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 678, __extension__ __PRETTY_FUNCTION__));
679 return reinterpret_cast<const error_type *>(&ErrorStorage);
680 }
681
682 // Used by ExpectedAsOutParameter to reset the checked flag.
683 void setUnchecked() {
684#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
685 Unchecked = true;
686#endif
687 }
688
689#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
690 [[noreturn]] LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) void fatalUncheckedExpected() const {
691 dbgs() << "Expected<T> must be checked before access or destruction.\n";
692 if (HasError) {
693 dbgs() << "Unchecked Expected<T> contained error:\n";
694 (*getErrorStorage())->log(dbgs());
695 } else
696 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
697 "values in success mode must still be checked prior to being "
698 "destroyed).\n";
699 abort();
700 }
701#endif
702
703 void assertIsChecked() const {
704#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
705 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
706 fatalUncheckedExpected();
707#endif
708 }
709
710 union {
711 AlignedCharArrayUnion<storage_type> TStorage;
712 AlignedCharArrayUnion<error_type> ErrorStorage;
713 };
714 bool HasError : 1;
715#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
716 bool Unchecked : 1;
717#endif
718};
719
720/// Report a serious error, calling any installed error handler. See
721/// ErrorHandling.h.
722[[noreturn]] void report_fatal_error(Error Err, bool gen_crash_diag = true);
723
724/// Report a fatal error if Err is a failure value.
725///
726/// This function can be used to wrap calls to fallible functions ONLY when it
727/// is known that the Error will always be a success value. E.g.
728///
729/// @code{.cpp}
730/// // foo only attempts the fallible operation if DoFallibleOperation is
731/// // true. If DoFallibleOperation is false then foo always returns
732/// // Error::success().
733/// Error foo(bool DoFallibleOperation);
734///
735/// cantFail(foo(false));
736/// @endcode
737inline void cantFail(Error Err, const char *Msg = nullptr) {
738 if (Err) {
739 if (!Msg)
740 Msg = "Failure value returned from cantFail wrapped call";
741#ifndef NDEBUG
742 std::string Str;
743 raw_string_ostream OS(Str);
744 OS << Msg << "\n" << Err;
745 Msg = OS.str().c_str();
746#endif
747 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 747);
748 }
749}
750
751/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
752/// returns the contained value.
753///
754/// This function can be used to wrap calls to fallible functions ONLY when it
755/// is known that the Error will always be a success value. E.g.
756///
757/// @code{.cpp}
758/// // foo only attempts the fallible operation if DoFallibleOperation is
759/// // true. If DoFallibleOperation is false then foo always returns an int.
760/// Expected<int> foo(bool DoFallibleOperation);
761///
762/// int X = cantFail(foo(false));
763/// @endcode
764template <typename T>
765T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
766 if (ValOrErr)
767 return std::move(*ValOrErr);
768 else {
769 if (!Msg)
770 Msg = "Failure value returned from cantFail wrapped call";
771#ifndef NDEBUG
772 std::string Str;
773 raw_string_ostream OS(Str);
774 auto E = ValOrErr.takeError();
775 OS << Msg << "\n" << E;
776 Msg = OS.str().c_str();
777#endif
778 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 778);
779 }
780}
781
782/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
783/// returns the contained reference.
784///
785/// This function can be used to wrap calls to fallible functions ONLY when it
786/// is known that the Error will always be a success value. E.g.
787///
788/// @code{.cpp}
789/// // foo only attempts the fallible operation if DoFallibleOperation is
790/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
791/// Expected<Bar&> foo(bool DoFallibleOperation);
792///
793/// Bar &X = cantFail(foo(false));
794/// @endcode
795template <typename T>
796T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
797 if (ValOrErr)
798 return *ValOrErr;
799 else {
800 if (!Msg)
801 Msg = "Failure value returned from cantFail wrapped call";
802#ifndef NDEBUG
803 std::string Str;
804 raw_string_ostream OS(Str);
805 auto E = ValOrErr.takeError();
806 OS << Msg << "\n" << E;
807 Msg = OS.str().c_str();
808#endif
809 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 809);
810 }
811}
812
813/// Helper for testing applicability of, and applying, handlers for
814/// ErrorInfo types.
815template <typename HandlerT>
816class ErrorHandlerTraits
817 : public ErrorHandlerTraits<decltype(
818 &std::remove_reference<HandlerT>::type::operator())> {};
819
820// Specialization functions of the form 'Error (const ErrT&)'.
821template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
822public:
823 static bool appliesTo(const ErrorInfoBase &E) {
824 return E.template isA<ErrT>();
825 }
826
827 template <typename HandlerT>
828 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
829 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 829, __extension__ __PRETTY_FUNCTION__));
830 return H(static_cast<ErrT &>(*E));
831 }
832};
833
834// Specialization functions of the form 'void (const ErrT&)'.
835template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
836public:
837 static bool appliesTo(const ErrorInfoBase &E) {
838 return E.template isA<ErrT>();
839 }
840
841 template <typename HandlerT>
842 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
843 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 843, __extension__ __PRETTY_FUNCTION__));
844 H(static_cast<ErrT &>(*E));
845 return Error::success();
846 }
847};
848
849/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
850template <typename ErrT>
851class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
852public:
853 static bool appliesTo(const ErrorInfoBase &E) {
854 return E.template isA<ErrT>();
855 }
856
857 template <typename HandlerT>
858 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
859 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 859, __extension__ __PRETTY_FUNCTION__));
860 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
861 return H(std::move(SubE));
862 }
863};
864
865/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
866template <typename ErrT>
867class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
868public:
869 static bool appliesTo(const ErrorInfoBase &E) {
870 return E.template isA<ErrT>();
871 }
872
873 template <typename HandlerT>
874 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
875 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 875, __extension__ __PRETTY_FUNCTION__));
876 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
877 H(std::move(SubE));
878 return Error::success();
879 }
880};
881
882// Specialization for member functions of the form 'RetT (const ErrT&)'.
883template <typename C, typename RetT, typename ErrT>
884class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
885 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
886
887// Specialization for member functions of the form 'RetT (const ErrT&) const'.
888template <typename C, typename RetT, typename ErrT>
889class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
890 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
891
892// Specialization for member functions of the form 'RetT (const ErrT&)'.
893template <typename C, typename RetT, typename ErrT>
894class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
895 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
896
897// Specialization for member functions of the form 'RetT (const ErrT&) const'.
898template <typename C, typename RetT, typename ErrT>
899class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
900 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
901
902/// Specialization for member functions of the form
903/// 'RetT (std::unique_ptr<ErrT>)'.
904template <typename C, typename RetT, typename ErrT>
905class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
906 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
907
908/// Specialization for member functions of the form
909/// 'RetT (std::unique_ptr<ErrT>) const'.
910template <typename C, typename RetT, typename ErrT>
911class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
912 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
913
914inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
915 return Error(std::move(Payload));
916}
917
918template <typename HandlerT, typename... HandlerTs>
919Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
920 HandlerT &&Handler, HandlerTs &&... Handlers) {
921 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
922 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
923 std::move(Payload));
924 return handleErrorImpl(std::move(Payload),
925 std::forward<HandlerTs>(Handlers)...);
926}
927
928/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
929/// unhandled errors (or Errors returned by handlers) are re-concatenated and
930/// returned.
931/// Because this function returns an error, its result must also be checked
932/// or returned. If you intend to handle all errors use handleAllErrors
933/// (which returns void, and will abort() on unhandled errors) instead.
934template <typename... HandlerTs>
935Error handleErrors(Error E, HandlerTs &&... Hs) {
936 if (!E)
937 return Error::success();
938
939 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
940
941 if (Payload->isA<ErrorList>()) {
942 ErrorList &List = static_cast<ErrorList &>(*Payload);
943 Error R;
944 for (auto &P : List.Payloads)
945 R = ErrorList::join(
946 std::move(R),
947 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
948 return R;
949 }
950
951 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
952}
953
954/// Behaves the same as handleErrors, except that by contract all errors
955/// *must* be handled by the given handlers (i.e. there must be no remaining
956/// errors after running the handlers, or llvm_unreachable is called).
957template <typename... HandlerTs>
958void handleAllErrors(Error E, HandlerTs &&... Handlers) {
959 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
960}
961
962/// Check that E is a non-error, then drop it.
963/// If E is an error, llvm_unreachable will be called.
964inline void handleAllErrors(Error E) {
965 cantFail(std::move(E));
966}
967
968/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
969///
970/// If the incoming value is a success value it is returned unmodified. If it
971/// is a failure value then it the contained error is passed to handleErrors.
972/// If handleErrors is able to handle the error then the RecoveryPath functor
973/// is called to supply the final result. If handleErrors is not able to
974/// handle all errors then the unhandled errors are returned.
975///
976/// This utility enables the follow pattern:
977///
978/// @code{.cpp}
979/// enum FooStrategy { Aggressive, Conservative };
980/// Expected<Foo> foo(FooStrategy S);
981///
982/// auto ResultOrErr =
983/// handleExpected(
984/// foo(Aggressive),
985/// []() { return foo(Conservative); },
986/// [](AggressiveStrategyError&) {
987/// // Implicitly conusme this - we'll recover by using a conservative
988/// // strategy.
989/// });
990///
991/// @endcode
992template <typename T, typename RecoveryFtor, typename... HandlerTs>
993Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
994 HandlerTs &&... Handlers) {
995 if (ValOrErr)
996 return ValOrErr;
997
998 if (auto Err = handleErrors(ValOrErr.takeError(),
999 std::forward<HandlerTs>(Handlers)...))
1000 return std::move(Err);
1001
1002 return RecoveryPath();
1003}
1004
1005/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
1006/// will be printed before the first one is logged. A newline will be printed
1007/// after each error.
1008///
1009/// This function is compatible with the helpers from Support/WithColor.h. You
1010/// can pass any of them as the OS. Please consider using them instead of
1011/// including 'error: ' in the ErrorBanner.
1012///
1013/// This is useful in the base level of your program to allow clean termination
1014/// (allowing clean deallocation of resources, etc.), while reporting error
1015/// information to the user.
1016void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
1017
1018/// Write all error messages (if any) in E to a string. The newline character
1019/// is used to separate error messages.
1020inline std::string toString(Error E) {
1021 SmallVector<std::string, 2> Errors;
1022 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
1023 Errors.push_back(EI.message());
1024 });
1025 return join(Errors.begin(), Errors.end(), "\n");
1026}
1027
1028/// Consume a Error without doing anything. This method should be used
1029/// only where an error can be considered a reasonable and expected return
1030/// value.
1031///
1032/// Uses of this method are potentially indicative of design problems: If it's
1033/// legitimate to do nothing while processing an "error", the error-producer
1034/// might be more clearly refactored to return an Optional<T>.
1035inline void consumeError(Error Err) {
1036 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
1037}
1038
1039/// Convert an Expected to an Optional without doing anything. This method
1040/// should be used only where an error can be considered a reasonable and
1041/// expected return value.
1042///
1043/// Uses of this method are potentially indicative of problems: perhaps the
1044/// error should be propagated further, or the error-producer should just
1045/// return an Optional in the first place.
1046template <typename T> Optional<T> expectedToOptional(Expected<T> &&E) {
1047 if (E)
1048 return std::move(*E);
1049 consumeError(E.takeError());
1050 return None;
1051}
1052
1053/// Helper for converting an Error to a bool.
1054///
1055/// This method returns true if Err is in an error state, or false if it is
1056/// in a success state. Puts Err in a checked state in both cases (unlike
1057/// Error::operator bool(), which only does this for success states).
1058inline bool errorToBool(Error Err) {
1059 bool IsError = static_cast<bool>(Err);
1060 if (IsError)
1061 consumeError(std::move(Err));
1062 return IsError;
1063}
1064
1065/// Helper for Errors used as out-parameters.
1066///
1067/// This helper is for use with the Error-as-out-parameter idiom, where an error
1068/// is passed to a function or method by reference, rather than being returned.
1069/// In such cases it is helpful to set the checked bit on entry to the function
1070/// so that the error can be written to (unchecked Errors abort on assignment)
1071/// and clear the checked bit on exit so that clients cannot accidentally forget
1072/// to check the result. This helper performs these actions automatically using
1073/// RAII:
1074///
1075/// @code{.cpp}
1076/// Result foo(Error &Err) {
1077/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1078/// // <body of foo>
1079/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1080/// }
1081/// @endcode
1082///
1083/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1084/// used with optional Errors (Error pointers that are allowed to be null). If
1085/// ErrorAsOutParameter took an Error reference, an instance would have to be
1086/// created inside every condition that verified that Error was non-null. By
1087/// taking an Error pointer we can just create one instance at the top of the
1088/// function.
1089class ErrorAsOutParameter {
1090public:
1091 ErrorAsOutParameter(Error *Err) : Err(Err) {
1092 // Raise the checked bit if Err is success.
1093 if (Err)
1094 (void)!!*Err;
1095 }
1096
1097 ~ErrorAsOutParameter() {
1098 // Clear the checked bit.
1099 if (Err && !*Err)
1100 *Err = Error::success();
1101 }
1102
1103private:
1104 Error *Err;
1105};
1106
1107/// Helper for Expected<T>s used as out-parameters.
1108///
1109/// See ErrorAsOutParameter.
1110template <typename T>
1111class ExpectedAsOutParameter {
1112public:
1113 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1114 : ValOrErr(ValOrErr) {
1115 if (ValOrErr)
1116 (void)!!*ValOrErr;
1117 }
1118
1119 ~ExpectedAsOutParameter() {
1120 if (ValOrErr)
1121 ValOrErr->setUnchecked();
1122 }
1123
1124private:
1125 Expected<T> *ValOrErr;
1126};
1127
1128/// This class wraps a std::error_code in a Error.
1129///
1130/// This is useful if you're writing an interface that returns a Error
1131/// (or Expected) and you want to call code that still returns
1132/// std::error_codes.
1133class ECError : public ErrorInfo<ECError> {
1134 friend Error errorCodeToError(std::error_code);
1135
1136 virtual void anchor() override;
1137
1138public:
1139 void setErrorCode(std::error_code EC) { this->EC = EC; }
1140 std::error_code convertToErrorCode() const override { return EC; }
1141 void log(raw_ostream &OS) const override { OS << EC.message(); }
1142
1143 // Used by ErrorInfo::classID.
1144 static char ID;
1145
1146protected:
1147 ECError() = default;
1148 ECError(std::error_code EC) : EC(EC) {}
1149
1150 std::error_code EC;
1151};
1152
1153/// The value returned by this function can be returned from convertToErrorCode
1154/// for Error values where no sensible translation to std::error_code exists.
1155/// It should only be used in this situation, and should never be used where a
1156/// sensible conversion to std::error_code is available, as attempts to convert
1157/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1158///error to try to convert such a value).
1159std::error_code inconvertibleErrorCode();
1160
1161/// Helper for converting an std::error_code to a Error.
1162Error errorCodeToError(std::error_code EC);
1163
1164/// Helper for converting an ECError to a std::error_code.
1165///
1166/// This method requires that Err be Error() or an ECError, otherwise it
1167/// will trigger a call to abort().
1168std::error_code errorToErrorCode(Error Err);
1169
1170/// Convert an ErrorOr<T> to an Expected<T>.
1171template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1172 if (auto EC = EO.getError())
1173 return errorCodeToError(EC);
1174 return std::move(*EO);
1175}
1176
1177/// Convert an Expected<T> to an ErrorOr<T>.
1178template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1179 if (auto Err = E.takeError())
1180 return errorToErrorCode(std::move(Err));
1181 return std::move(*E);
1182}
1183
1184/// This class wraps a string in an Error.
1185///
1186/// StringError is useful in cases where the client is not expected to be able
1187/// to consume the specific error message programmatically (for example, if the
1188/// error message is to be presented to the user).
1189///
1190/// StringError can also be used when additional information is to be printed
1191/// along with a error_code message. Depending on the constructor called, this
1192/// class can either display:
1193/// 1. the error_code message (ECError behavior)
1194/// 2. a string
1195/// 3. the error_code message and a string
1196///
1197/// These behaviors are useful when subtyping is required; for example, when a
1198/// specific library needs an explicit error type. In the example below,
1199/// PDBError is derived from StringError:
1200///
1201/// @code{.cpp}
1202/// Expected<int> foo() {
1203/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1204/// "Additional information");
1205/// }
1206/// @endcode
1207///
1208class StringError : public ErrorInfo<StringError> {
1209public:
1210 static char ID;
1211
1212 // Prints EC + S and converts to EC
1213 StringError(std::error_code EC, const Twine &S = Twine());
1214
1215 // Prints S and converts to EC
1216 StringError(const Twine &S, std::error_code EC);
1217
1218 void log(raw_ostream &OS) const override;
1219 std::error_code convertToErrorCode() const override;
1220
1221 const std::string &getMessage() const { return Msg; }
1222
1223private:
1224 std::string Msg;
1225 std::error_code EC;
1226 const bool PrintMsgOnly = false;
1227};
1228
1229/// Create formatted StringError object.
1230template <typename... Ts>
1231inline Error createStringError(std::error_code EC, char const *Fmt,
1232 const Ts &... Vals) {
1233 std::string Buffer;
1234 raw_string_ostream Stream(Buffer);
1235 Stream << format(Fmt, Vals...);
1236 return make_error<StringError>(Stream.str(), EC);
1237}
1238
1239Error createStringError(std::error_code EC, char const *Msg);
1240
1241inline Error createStringError(std::error_code EC, const Twine &S) {
1242 return createStringError(EC, S.str().c_str());
1243}
1244
1245template <typename... Ts>
1246inline Error createStringError(std::errc EC, char const *Fmt,
1247 const Ts &... Vals) {
1248 return createStringError(std::make_error_code(EC), Fmt, Vals...);
1249}
1250
1251/// This class wraps a filename and another Error.
1252///
1253/// In some cases, an error needs to live along a 'source' name, in order to
1254/// show more detailed information to the user.
1255class FileError final : public ErrorInfo<FileError> {
1256
1257 friend Error createFileError(const Twine &, Error);
1258 friend Error createFileError(const Twine &, size_t, Error);
1259
1260public:
1261 void log(raw_ostream &OS) const override {
1262 assert(Err && !FileName.empty() && "Trying to log after takeError().")(static_cast <bool> (Err && !FileName.empty() &&
"Trying to log after takeError().") ? void (0) : __assert_fail
("Err && !FileName.empty() && \"Trying to log after takeError().\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 1262, __extension__ __PRETTY_FUNCTION__));
1263 OS << "'" << FileName << "': ";
1264 if (Line.hasValue())
1265 OS << "line " << Line.getValue() << ": ";
1266 Err->log(OS);
1267 }
1268
1269 StringRef getFileName() { return FileName; }
1270
1271 Error takeError() { return Error(std::move(Err)); }
1272
1273 std::error_code convertToErrorCode() const override;
1274
1275 // Used by ErrorInfo::classID.
1276 static char ID;
1277
1278private:
1279 FileError(const Twine &F, Optional<size_t> LineNum,
1280 std::unique_ptr<ErrorInfoBase> E) {
1281 assert(E && "Cannot create FileError from Error success value.")(static_cast <bool> (E && "Cannot create FileError from Error success value."
) ? void (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 1281, __extension__ __PRETTY_FUNCTION__));
1282 assert(!F.isTriviallyEmpty() &&(static_cast <bool> (!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? void (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 1283, __extension__ __PRETTY_FUNCTION__))
1283 "The file name provided to FileError must not be empty.")(static_cast <bool> (!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? void (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-14~++20210828111110+16086d47c0d0/llvm/include/llvm/Support/Error.h"
, 1283, __extension__ __PRETTY_FUNCTION__));
1284 FileName = F.str();
1285 Err = std::move(E);
1286 Line = std::move(LineNum);
1287 }
1288
1289 static Error build(const Twine &F, Optional<size_t> Line, Error E) {
1290 std::unique_ptr<ErrorInfoBase> Payload;
1291 handleAllErrors(std::move(E),
1292 [&](std::unique_ptr<ErrorInfoBase> EIB) -> Error {
1293 Payload = std::move(EIB);
1294 return Error::success();
1295 });
1296 return Error(
1297 std::unique_ptr<FileError>(new FileError(F, Line, std::move(Payload))));
1298 }
1299
1300 std::string FileName;
1301 Optional<size_t> Line;
1302 std::unique_ptr<ErrorInfoBase> Err;
1303};
1304
1305/// Concatenate a source file path and/or name with an Error. The resulting
1306/// Error is unchecked.
1307inline Error createFileError(const Twine &F, Error E) {
1308 return FileError::build(F, Optional<size_t>(), std::move(E));
1309}
1310
1311/// Concatenate a source file path and/or name with line number and an Error.
1312/// The resulting Error is unchecked.
1313inline Error createFileError(const Twine &F, size_t Line, Error E) {
1314 return FileError::build(F, Optional<size_t>(Line), std::move(E));
1315}
1316
1317/// Concatenate a source file path and/or name with a std::error_code
1318/// to form an Error object.
1319inline Error createFileError(const Twine &F, std::error_code EC) {
1320 return createFileError(F, errorCodeToError(EC));
1321}
1322
1323/// Concatenate a source file path and/or name with line number and
1324/// std::error_code to form an Error object.
1325inline Error createFileError(const Twine &F, size_t Line, std::error_code EC) {
1326 return createFileError(F, Line, errorCodeToError(EC));
1327}
1328
1329Error createFileError(const Twine &F, ErrorSuccess) = delete;
1330
1331/// Helper for check-and-exit error handling.
1332///
1333/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1334///
1335class ExitOnError {
1336public:
1337 /// Create an error on exit helper.
1338 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1339 : Banner(std::move(Banner)),
1340 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1341
1342 /// Set the banner string for any errors caught by operator().
1343 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1344
1345 /// Set the exit-code mapper function.
1346 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1347 this->GetExitCode = std::move(GetExitCode);
1348 }
1349
1350 /// Check Err. If it's in a failure state log the error(s) and exit.
1351 void operator()(Error Err) const { checkError(std::move(Err)); }
1352
1353 /// Check E. If it's in a success state then return the contained value. If
1354 /// it's in a failure state log the error(s) and exit.
1355 template <typename T> T operator()(Expected<T> &&E) const {
1356 checkError(E.takeError());
1357 return std::move(*E);
1358 }
1359
1360 /// Check E. If it's in a success state then return the contained reference. If
1361 /// it's in a failure state log the error(s) and exit.
1362 template <typename T> T& operator()(Expected<T&> &&E) const {
1363 checkError(E.takeError());
1364 return *E;
1365 }
1366
1367private:
1368 void checkError(Error Err) const {
1369 if (Err) {
1370 int ExitCode = GetExitCode(Err);
1371 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1372 exit(ExitCode);
1373 }
1374 }
1375
1376 std::string Banner;
1377 std::function<int(const Error &)> GetExitCode;
1378};
1379
1380/// Conversion from Error to LLVMErrorRef for C error bindings.
1381inline LLVMErrorRef wrap(Error Err) {
1382 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1383}
1384
1385/// Conversion from LLVMErrorRef to Error for C error bindings.
1386inline Error unwrap(LLVMErrorRef ErrRef) {
1387 return Error(std::unique_ptr<ErrorInfoBase>(
1388 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1389}
1390
1391} // end namespace llvm
1392
1393#endif // LLVM_SUPPORT_ERROR_H